China is having a 'big day' after Trump-Kim summit: Ex-diplomats

The agreement between President Donald Trump and North Korea's Kim Jong Un in Singapore represents a "big day" for China, two former U.S. diplomats told CNBC on Tuesday.

"China would love American troops to be gone from the Korean Peninsula," Wendy Sherman, a former undersecretary of state for political affairs, said in a "Squawk Box" interview.

In her role, Sherman oversaw several bureaus, including East Asia, the Near East, South and Central Asia.

"China understands that this discussion is not just about North Korea, it's about the future of Northeast Asia," added Sherman, who was a special advisor to former President Bill Clinton. "China wants to be in charge of it."

Trump and Kim signed what's being called a comprehensive denuclearization agreement at the conclusion of Tuesday's historic summit in Singapore. As a part of the deal, Trump said the U.S. will be stopping the war games it conducts near North Korea. The president also said he would eventually like to see the full withdrawal of U.S. troops from the Korean Peninsula.

China has key strategic interests when it comes to North Korea. It has long feared that a collapse of its isolated neighbor could push waves of refugees into northeastern China, or that nuclear war on the Korean Peninsula could contaminate swathes of the country.

On Tuesday, China took a decidedly positive toneon the agreement.

Max Baucus, U.S. ambassador to China under former President Barack Obama from 2014 to 2017, also told "Squawk Box" that China is likely "generally pleased" with the agreement, adding China would like the U.S. to leave South Korea.

China "is looking at the long ball," said Baucus, also a former United States senator. "They're very patient. They're working very hard. And don't forget, China is an 800-pound gorilla there. They're large and proximity is power."