Live from ABC News headquarters in New York City.

This is Good Morning America.

We begin with President Trump's mission to China.

He had his first meeting with Chinese President Xi, Iran high in the agenda, and she delivered a tough morning on Taiwan.

Chief White House correspondent Mary Bruce is in Beijing with the latest.

Good morning, Mary. Good morning, Mary.

Good morning, George. And so far this summit has had all of the pomp and ceremony that you would expect from the leaders of the two most powerful nations.

But hanging over all of this, as you said, the war in Iran. And now that new stark warning from China to the U.S.

Overnight, the high stakesstakes handshake between superpowers.

Chinese President Xi welcoming President Trump back to China for the first time in nearly a decade.

Rolling out the red carpet.

Chinese children there to greet Trump. After the pomp, Trump heap heaping praise on Xi.

You're a great leader.

Sometimes people don't like me saying it, but I say it anyway because it's true.

Sitting with their delegations at an expansive negotiating table,

Xi saying they should be partners, not adversaries, that their common interests

outweigh their differences.

But the pleasantries a stark contrast to the challenges facing this critical relationship.

In their over two-hour meeting, Xi delivering a stark warning to Trump about Taiwan, which

Beijing claims is its own territory.

According to China's state media, Xi telling Trump, if the issue is handled poorly,

the two countries will collide or even clash.

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