Philippine President Rodrigo Duterte has apologised for his "hurting words" about two tycoons whom he openly dislikes, responding to their help in fighting the coronavirus by offering an olive branch to settle a costly regulatory row.

Shares in conglomerates Ayala Corp and Metro Pacific Investments Corp, owners of the country's two largest water distributors, climbed on Tuesday following the president's late night apology.

"So maybe there will be a lot of legal issues but we can talk. I am ready to talk and I would be reasonable," Duterte said during a televised speech.

"My hurtful words to the Ayalas and to (Manuel) Pangilinan, I apologise for the hurting words," he said, adding that the novel coronavirus outbreak had humbled him.

During his four years in office, Duterte has repeatedly lashed out at Pangilinan and the Ayala family for numerous reasons. The billionaires typically do not comment on his remarks.

Between them, their firms have a telecoms duopoly and major interests in real estate, retail, renewable energy, healthcare, power, education and infrastructure.

The Philippines was among the first countries to enforce strict home quarantine measures against coronavirus, which has infected 9,485 people in the country and killed 623 of them.

The capital, Manila, and several other urban centres have been under a strict lockdown for nearly seven weeks.

Private firms have donated much-needed protective gear and other supplies to hospitals and the public, plugging some gaps in government efforts.

Ayala Corp rose as much as 8.5% while subsidiary Manila Water Co Inc spiked up to 13.2% and infrastructure conglomerate Metro Pacific rose as much as 11.6%, all outpacing the 1.8% uptick of the broader index.

Duterte had criticised contracts of Manila Water and Metro Pacific's Maynilad Water "onerous and disadvantageous" to the public and threatened to strip them of their concessions.

His public barbs since December have caused big share price losses for the companies, and rattled investors already wary about regulatory risks from Duterte's notorious volatility and his influence over courts and Congress.

The companies' concessions, which allow them to service a combined 16 million customers mostly in the capital, will expire in 2022 but are subject to a 15-year extension under review.

In a statement, Ayala's top executives welcomed Duterte's comments, committing to help the government to save lives and gradually put the country back on a growth path.

Pangilinan also welcomed Duterte's remarks, saying his group was willing to work with the government.

(Reporting by Neil Jerome Morales; Editing by Martin Petty, Robert Birsel)