Secretary of State Mike Pompeo says joint U.S.-South Korea military exercises will resume if North Korea stops negotiating in good faith over its nuclear program.

Pompeo is in South Korea a day after President Donald Trump met with Kim Jong Un and announced the U.S. would freeze what he called "war games" with North Korea.

Pompeo says he was there when Trump talked about it with Kim. He says Trump "made very clear" that the condition for the freeze was that good-faith talks continue. He says if the U.S. concludes they no longer are in good faith, the freeze "will no longer be in effect."

Pompeo says Trump was "unambiguous" in conveying that to Kim.

Earlier, President Trump defended his calls to end the military exercises with South Korea.

Trump said on Twitter after returning from his Singapore summit that "we save a fortune by not doing war games, as long as we are negotiating in good faith."

Back in the United States, Trump is tweeting about his historic summit with North Korean leader Kim Jong Un. He says there is no longer a nuclear threat from North Korea even though experts estimate that Kim's government has enough fissile material for 20 to 60 bombs.

Meanwhile, President Trump's triumphant assertions about the summit are being met with skepticism and outright derision from some critics.

They're seizing on the contradiction between Trump's withdrawal from the Iran nuclear deal and his willingness to accept vague pledges from North Korea's Kim Jong Un.

White House officials stress that this week's meeting in Singapore is the beginning of a process and not its end.

The Singapore summit sets out broad goals to be met in the coming months. In contrast, the Iran deal, signed by President Barack Obama in 2015 and approved by seven nations, followed 18 months of talks.

The chairman of the Senate Foreign Affairs Committee, Tennessee Republican Bob Corker, says it's difficult to determine what of a concrete nature has taken place.

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