Chilean President Sebastian Pinera says protests roiling the country have pushed him to call off two major international summits that his country had been scheduled to host.

Key points: Mr Pinera says he needs to "put the needs of compatriots first"

Mr Pinera says he needs to "put the needs of compatriots first" It is unclear if this year's summits will be moved to other countries

It is unclear if this year's summits will be moved to other countries The UN is considering using its own venues for its climate change summit

Mr Pinera said on Wednesday (local time) Chile would not host the Asia-Pacific Economic Cooperation (APEC) summit set for November 16–17 and the UN's global climate gathering, COP25, planned for December 2–13.

The Chilean President did not mention a possible alternative venue for the APEC summit.

"This has been a very difficult decision that causes us great pain," Mr Pinera said in a televised address.

"A president always has to put the needs of his compatriots first."

Riots, arson and protests over inequality this month have left at least 18 people dead, 7,000 arrested and Chilean businesses hit with losses of about $US1.4 billion ($2 billion).

The metro public transport system in the capital suffered nearly $US400 million in damages.

Chile's embattled leader fired almost half his cabinet this week — including his finance, interior and economy ministers — in a bid to quell the protests but to little effect.

With Mr Pinera's popularity at an all-time low, Chileans are calling for new protests while the United Nations (UN) is sending a team to investigate allegations of human rights abuses by security forces.

Subway stations in Santiago have been torched amid the unrest. ( AP: Rodrigo Abd )

The cancellations are a further blow to Chile's much-vaunted image as one of the most stable countries in Latin America.

The APEC summit was scheduled to bring together 20 world leaders, including US President Donald Trump and Chinese President Xi Jinping, on November 16–17.

US and Chinese negotiators were hoping to finalise a modest trade agreement in time so that Mr Trump and Mr Xi could sign it at the APEC summit in Santiago.

Under the tentative deal, the US had agreed to suspend plans to raise tariffs on $US250 billion in Chinese imports, and Beijing had agreed to step up purchases of US farm products.

Chile's cancellation of the trade summit caught the Trump administration by surprise, a White House official told Reuters.

The official said Washington learned about the decision from news reports and was seeking more information.

COP25 may be held in existing UN venues

Mr Pinera is facing unprecedented unrest in one of South America's most stable democracies. ( Luis Hidalgo: AP )

The UN is looking for a new venue for the conference after Mr Pinera spoke with UN Secretary-General Antonio Guterres by phone on Wednesday to inform him of Chile's withdrawal, a UN spokesperson said.

Those would include cities such as New York, Geneva, Bonn, Vienna and Nairobi.

The climate summit would have brought delegates from about 190 nations to talks aimed at thrashing out details of how to reduce global emissions to meet the Paris climate agreement.

Santiago's streets have been sites of violent clashes between police and protesters. ( AP: Esteban Felix )

AP/Reuters