Obama faces tough questions about Trump on his last foreign trip

The US president and other top world leaders, including China's Xi Jinping and Russia's Vladimir Putin, are in Lima, Peru, for an Asia-Pacific Economic Cooperation (APEC) summit whose staid agenda has been hijacked by the Republican billionaire's shock election win last week.

On Saturday, Obama is meeting leaders of the 12 countries negotiating the Trans-Pacific Partnership, or TPP, a vast US-led trade accord that Trump opposes and now faces an uncertain future.

Although the White House admits the chances of passing the deal are slim, Obama will urge leaders to give the new president time to formulate his policy.

From Obama down, officials have stressed that the election has not changed US economic and strategic interests, and that Trump may yet recalibrate his views.

But there is little chance Trump's Republican allies in Congress would ratify TPP anytime soon.

"That is a real blow to US interests, economically and strategically, in terms of our position in Asia, but I think that is the reality, that the US is not going to be participating," said Matthew Goodman, an expert on Asian economics with the Center for Strategic and International Studies.

"But there are 11 other countries in TPP and I think that it is possible that they will agree to go ahead and pass TPP," he added in an interview, saying the others could "tweak" the agreement to keep it alive without US participation.

Turning to China

Some allies are turning their attention to a rival Chinese-backed free-trade agreement.

Japanese leader Shinzo Abe, who took domestic political risks to back TPP, visited Trump in New York on Thursday to hear from the president-elect himself.

The real estate mogul has prompted concern in Japan and South Korea in particular by questioning decades-old mutual defense obligations that underpin their security.

National Security Advisor Susan Rice said ahead of Obama's visit that allies should expect those obligations to hold.

"It is manifestly in the United States' interests for these alliances to endure and to be a source of confidence to our partners and for them to understand that they don't need to come out from under the US umbrella," she told AFP.

Stressing that she did not want to speculate about Trump's foreign policy, she sought to reassure key US allies in NATO and the Pacific Rim that they will not be abandoned.

Many Pacific countries are clamoring for deeper trade ties with the rest of the world.

But in the United States and throughout the West, opposition is growing to deals that many say have contributed to jobs being sent overseas.

Obama is likely to make the case that globalization is a fact of life, and modern trade deals — with sturdy environmental and labor provisions — help shape that trend in the right direction.

Nuclear Korea

Obama is also set to hold talks with the leaders of Russia, Canada, Australia, Peru and, crucially, China's Xi — the final meeting between the leaders of the world's two largest economic powers.

The sit-down will also deal with efforts to stop North Korea's ballistic missile and nuclear programs, US officials say.

Obama is expected to press for an increase in the pace and severity of sanctions against North Korea, which is trying to develop a miniaturized nuclear warhead and a missile capable of delivering the weapon to the United States.

Beijing has long dragged its heels over sanctioning its allies in Pyongyang, fearing a flood of refugees if North Korea's economy collapses.

But earlier this year, China moved to sanction a conglomerate based in its frontier city of Dandong that had an estimated $530 million in trade with North Korea between 2011 and 2015.