Antofagasta : Publication of 2020 Annual Report and 2021 Notice of AGM...

NEWS RELEASE, 7 APRIL 2021

PUBLICATION OF 2020 ANNUAL REPORT AND 2021 NOTICE OF ANNUAL

GENERAL MEETING AND CLASS MEETINGS

Antofagasta plc (the "Company") has today posted its 2020 Annual Report and Financial Statements and notice of the Annual General Meeting and class meetings of the Company (the "2021 Notice of AGM and Class Meetings") to shareholders.

The 2020 Annual Report and Financial Statements, which were approved by the Board of Directors on 15 March 2021, constitute the Company's statutoryaccounts for the purposes of section 434of the Companies Act 2006 and the Annual Financial Report for the purposes of DTR 4.1.

The Annual General Meeting will be held at the Company's offices at Cleveland House, 33 King Street, London SW1Y 6RJ on 12 May 2021 from 2 p.m. Separate meetings of the ordinary shareholders and preference shareholders (the"Class Meetings") willfollow directly after the Annual General Meeting.

Due to the ongoing COVID-19 pandemic, the Board anticipate that the meetings will go ahead as planned but that shareholders will not be able to attend in person. A separate RNS announcement, including details for remote engagement, will be published today in relation to these arrangements.

In compliance with LR 9.6.1, the Company has submitted to the Financial Conduct Authority each of the following documents:

• 2020 Annual Report and Financial Statements
• 2021 Notice of AGM and Class Meetings
• Letter to Shareholders regarding Arrangements for the Annual GeneralMeeting and Class Meetings, which is supplementary to, and must be read in conjunction with, the 2021 Notice of AGM and Class Meetings.
• Form of Proxy for Ordinary Shareholders for Annual General Meeting
• Form of Proxy for Preference Shareholders for Annual General Meeting
• Form of Proxy for Ordinary Shareholders for Class Meeting
• Form of Proxy for Preference Shareholders for Class Meeting
• Letter to Shareholders regarding Electronic Communications

These documents will shortly be available for inspection via the National Storage Mechanism, (www.morningstar.co.uk/uk/NSM).

In compliance with DTR 6.3.5, the following information is extracted from the 2020 Annual Report and Financial Statements and should be read in conjunction with the Company's Preliminary Results Announcement issued on 16 March 2021. Together, these constitutethe material required by DTR 6.3.5 to be communicated to the media in fullunedited text through a Regulatory Information Service.This material is not a substitute for reading the full 2020 Annual Report and Financial Statements and page numbers and cross-references inthe extractedinformation belowrefer to page numbers and cross-referencesin the 2020

Annual Report and Financial Statements. The full 2020 Annual Report and Financial Statements and materials relating to the Annual General Meeting and the Class Meetings are available on the Company's website at (www.antofagasta.co.uk).

The information contained in this announcement and in the Preliminary Results Announcement does not constitute the Group's statutory accounts as defined in section 434 of the Companies Act 2006, but is derived from those accounts. The statutory accounts for the year ended 31 December 2020 have been approved by the Board and will be delivered to the Registrar of Companies following the Company's Annual General Meeting. The auditors have reported on those accounts and their report was unqualified, with no matters by way of emphasis, and did not contain statements under section 498(2) of the Companies Act 2006 (regarding adequacy of accounting records and returns) or under section 498(3) (regarding provision of necessary information and explanations).

Statement of Directors' Responsibilities

The following information is extracted from page 155 of the 2020 Annual Report and Financial Statements.

"The directors consider that the annual report and accounts, taken as a whole, is fair, balanced and understandable and provides the information necessary for shareholders to assess the group's and parent company's position and performance, business modeland strategy.

Each of the directors, whose names and functions are listed in the Corporate Governance Report, confirm that, to the best of their knowledge:

• the group financialstatements, which have been prepared in accordance with international accounting standards in conformity with the requirements of the Companies Act 2006 and internationalfinancialreporting standards adopted pursuant to Regulation (EC) No 1606/2002 as it applies in the European Union, give a true and fair view of the assets, liabilities, financialposition and profit of the group;
• the parent company financialstatements,which have been prepared in accordance with United Kingdom Accounting Standards, comprising FRS 101, give a true and fair view of the assets, liabilities, financialposition and profit of the parent company; and
• the Strategic Report includes a fair review of the development and performance of the business and the position of the group and parent company, together with a description of the principal risks and uncertainties that it faces.

By order of the Board

Jean-PaulLuksic, Chairman

Ollie Oliveira, Senior Independent Director"

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Principal Risks and Uncertainties

The following description of PrincipalRisks and Uncertainties is extracted from pages 25 to 30 of the 2020 Annual Report and Financial Statements.

"1. Talent management

Managing talent and maintaining a high-quality labour force in a changing technological and cultural environment is a key priority for us. Any failures in this respect could have a negative impact on the performance of the existing operations and prospects for future growth.

Preventive and mitigation measures

We develop the talents of our employees through training and career development, invest in initiatives to widen the talent pooland are committed to our diversity and inclusion policy. Through these actions we aim to increase employee retention, as well as the number of women, people with disabilities and employees with internationalexperience in the workplace.

Our Employee Performance Management Systemis designed to attract and retain key employees bycreating suitable reward and remuneration structures andprovidingpersonal development opportunities. We have a talent management system to identify and develop internal candidates for key management positions, as well as identifying suitable external candidates when appropriate.

Highlights

During 2020 our Group leadership frameworkwas released, the diversity andinclusion strategywas strongly promoted and a new remote working standard was launched.

2. Labour relations

Our highly skilled workforce and experienced management team are critical to maintaining our current operations, implementing development projects and achieving long-term growth without major disruption.

Preventive and mitigation measures

We maintain good relations with our employees and unions, which are founded on trust, regular dialogue and good working conditions. We are committed to safety, non-discrimination, diversity and inclusion, and compliance with Chile's strict labour regulations.

There are long-term labour agreements in place with all the unions at our operations, helping to ensure labour stability.

We seek to identify and address labour issues that may arise throughout the period covered by the labour agreements (usually three years) and to anticipate any potential issues in good time. Contractors are an important part of our workforce and under Chilean law are subject to the same duties and responsibilities as our own employees. We treat contractors as strategic associates and build long-term, mutually beneficial relationships with them.

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We maintain constructive relationships with our employees andtheir unions throughregular communication and consultation. Union representatives are regularly involved in discussions about the future of the workforce.

Highlights

Ten labour negotiations took place in 2020. In all cases, the Company andlabour representatives successfully reached agreement.

3. Safety and health

Safety and health incidents could result in harm to our employees, contractors and local communities. Ensuring their safety and wellbeing is our ethical obligation and first priority and is one of our core values. A poor safety record or serious accidents could have a long-term impact on morale and on Antofagasta's reputation and production.

Preventive and mitigation measures

We seek to continuously improve our safety and health risk management procedures, with particular focus on the early identification of risks and the prevention of fatalities.

The Corporate Safety and Health Department provides a common strategy for our operations and coordinates all safety and health matters. We have a Significant Incident Report system, which is an important part of the overall approach to safety.

Our goals of zero serious accidents and fatalities and the minimising of the number of accidents require all contractors to comply with our OccupationalSafetyand Health Plan. This plan is monitored throughmonthly audits and is supported by regular training and awareness campaigns for employees, contractors, employees' families and local communities, particularly with regard to road safety. We require all staff in defined safety-criticalroles to satisfy at least the minimum qualifications, to have the necessary experience for their role and to complete any required training prior to commencing their work activities.

Critical controls and verification tools are regularly strengthened through the verification programme and regular audits of critical controls for potentially high-risk activities.

We continuously seek to incorporate technology and innovation to reduce workers' exposure to safety and health risks.

Highlights

In 2020 there were no fatal accidents. The COVID-19 outbreak threatened the health of all employees and contractors, and local communities. We focused on implementing controls to prevent and mitigate the impact of infection, prioritising the health of our employees and contractors while minimising the impact on operationalcontinuity.

4. Environmental management

An operating incident that damages the environment could affect both our relationship with local stakeholders and our reputation, reducing the socialvalue we generate.

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We operate in challenging environments, including the largely agricultural Choapa Valley and the Atacama Desert, where water scarcity is a key issue.

Preventive and mitigation measures

We have a comprehensive approach to incident prevention. Relevant risks are assessed, monitored and controlled in order to achieve our goalof zero incidents with significant environmentalimpact. We work to raise awareness among employees and contractors, providing training to promote operatingexcellence. The potential environmental impact of a project is a key consideration when assessing its viability, and we encourage the integration of innovative technology in the project design to mitigate such impacts.

We prioritise the efficient use of natural renewable resources by using sea water, favouring the use of renewable power sources, achieving higher rates of reuse and recovery of water through thickened tailings technology and reducing greenhouse gas emissions.

We recognise that environmental sustainability is key to our ability to generate social value and perform regular risk assessments in order to identify potential impacts and develop preventive and mitigating strategies.

Each site maintains updated environmental emergency preparedness and detailed closure plans with appropriate financialprovisions to ensure physicaland chemicalstability once operations have ceased.

Highlights

We had no significant environmentalincidents during 2020.

We monitored and reinforced our critical controls in line with our low appetite for environmentalrisk.

5. Climate change

The effects of climate change have had an increasing impact on our operations. The drought in the central area of Chile is affecting water availability, while higher than expected rainfall in the northern part of the country is impacting the infrastructure in the region and the increasing severity of sea swells are leading to delays in the delivery of key supply materials.

We are committed to contributing to the reduction of the global problem of growing greenhouse gas emissions and water scarcity by reducing our own emissions. We can do this by increasing the amount of power and water we obtain from renewable and sustainable sources.

Preventive and mitigation measures

We recognise that climate change is a threat to human life and the planet as we know it today.

We measure and report our greenhouse gas emissions and have committed to reduction targets based on realistic plans.

As regards water scarcity, we are reducing our dependence on continental water through improved water use efficiency and the increased use of sea water as a total proportion of our water consumption. On completion of each phase of the Los Pelambresdesalination plant construction, the proportionof continental water used will decrease and significantly lower the potentialimpact of water scarcity on the Group.

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