WASHINGTON, United States (AFP) — President Barack Obama hosted a triumphant Donald Trump in the Oval Office Thursday for talks on executing a smooth transition of power and steadying nerves after a vote that shocked the world.

Anger over the Republican property mogul’s upset election win over Hillary Clinton spilled out onto the streets of US cities late Wednesday as chanting protesters lit bonfires and snarled traffic.

The billionaire president-elect arrived at his soon-to-be home on Pennsylvania Avenue at roughly 11:00 am (1600 GMT), a US official said, for what may be an awkward meeting with Obama ahead of the January 20 inauguration.

Trump, 70, championed the so-called “birther movement” challenging that Obama was actually born in the United States — a suggestion laden with deep racial overtones — only dropping the position recently.

The Democratic commander-in-chief in turn has described the celebrity businessman as “uniquely unqualified” to be president.

But in the day after Trump’s shock election win, which virtually no poll had predicted, both sides spoke of healing the deep divisions sown in a bruising two-year battle for the White House.

His vanquished Democratic rival Clinton, holding back the bitter disappointment of not becoming America’s first female president, urged the country to give Trump a chance.

“We owe him an open mind and the chance to lead,” she said Wednesday in a concession speech.

Obama, addressing disconsolate staff in the White House Rose Garden, played down Trump’s win as part of the messy “zig-zag” movement of a democracy. 

“Sometimes you lose an argument,” he said, adding that all Americans should now be “rooting” for Trump’s success.

In the battle for the soul of America, those who helped elect its first black president now appear to be in retreat and pondering whether his eight years in power have come to naught.

Both Obama and Clinton issued a faint — but clear — warning that Trump must respect institutions and the rule of law if a modicum of goodwill is to hold.

Trump’s tone, indicated White House spokesman Josh Earnest, “would seem to suggest that certain basic principles of our democracy are likely to be upheld.”

– Cooperation with allies  –

That “likely” observance of rule of law may not suffice for Washington’s partners and allies, who see an entire global political order built around US leadership cast into doubt.

German Chancellor Angela Merkel was quick to underscore the importance of shared democratic values. 

“On the basis of these values, I offer close cooperation to the future president of the United States of America,” she said.

Europe, already beset by financial and social crises and internal divisions, now faces existential questions about its own security. Trump has questioned the US-led NATO’s key collective defense guarantee.

The leaders of America’s neighbors, Canada and Mexico, quickly made clear their willingness to work with the new president.

President Enrique Pena Nieto of Mexico, a prime target of Trump’s anti-immigration campaign rhetoric, reached out to congratulate the incoming leader and announced they would soon meet.

– ‘Help wanted’ –

The Republican Party leadership, too, embraced their newfound champion.

House Speaker Paul Ryan, who had distanced himself from Trump in the final month of the campaign, pledged to “hit the ground running” and work with him on conservative legislation.

The two, along with Vice President-elect Mike Pence, were to meet on Capitol Hill after Trump’s talks with Obama.

On Wednesday, Trump huddled at Trump Tower in New York with a group of advisers, planning a transition strategy to take over stewardship of the world’s largest economy.

Team Trump unveiled a transition website — www.greatagain.gov — that highlights the colossal human resources challenge facing the incoming administration under the headline “Help wanted: 4,000 presidential appointees.”

It features a biography introducing the president-elect as “the very definition of an American success story, continually setting the standards of excellence for real estate, sports and entertainment” and invites the public to share ideas on “Making America Great Again.” 

During a bitter campaign that tugged at America’s democratic fabric, the tycoon pledged to deport illegal immigrants, ban Muslims from the country and tear up free-trade deals.

Those campaign messages were embraced by a large section of America, grown increasingly disgruntled by the scope of social and economic change under Obama.

But they were passionately rejected by Clinton supporters.

Thousands of protesters — in New York, Los Angeles, Boston, Chicago, Philadelphia, Portland and other cities and school campuses — rallied Wednesday to express continued opposition to the incoming leader they accuse of racism, sexism and xenophobia.

In Los Angeles, a giant Trump head was burned in effigy.