MILAN, April 7 (Reuters) - Italy's government, the country's main unions and employer associations said on Wednesday they had signed a protocol to organise the administration of vaccines in workplaces, as Rome steps up its vaccination plan.

Companies are eager to resume full activity in Italy, one of the European countries worst-hit by COVID-19, after businesses have been heavily impacted by the restrictions that Rome has imposed for over a year to stem the contagion of coronavirus.

Under the agreement, companies or groups of companies can submit their plans for voluntary employee vaccinations to local health authorities and make premises and internal medical staff available to do so.

Alternatively, companies will also be allowed to sign agreements with private medical service suppliers to have their employees vaccinated.

While health authorities will still provide the vaccines - once doses are available - needles, syringes and specific training for staff, employers will bear the costs of setting up and managing the vaccinations.

Italy has said it aims to vaccinate at least 80% of its population by the end of September, following criticism about the slow rollout of its campaign.

As of Wednesday afternoon, 11.6 million shots had been administered in the country, with 3.6 million of its 60-million-strong population having received the recommended two doses.

Medical staff who will vaccinate in the companies will not be held liable for any adverse health events after the jabs.

"As soon as the vaccine availability will make it possible, this will give a strong boost to the national vaccination campaign," Italy's largest employers lobby Confindustria said in a statement.

Confindustria last month launched a survey among companies to find out which ones were willing to take part in the country's vaccination effort. Almost 7,500, including TIM , Enel and Pirelli have signed up to the initiative.

Rome is also in direct talks with some large corporations, including Stellantis, to use their premises as hubs for its nationwide vaccination campaign.

(Reporting by Giulio Piovaccari; editing by David Evans)