BEIJING/UNITED NATIONS (Reuters) – U.S. President Donald Trump and Chinese President Xi Jinping exchanged a short duel of barbs on the eve of a U.N. General Assembly anniversary in which the leaders also clashed over North Korea and support for a new round of U.N. sanctions.

FILE PHOTO: U.S. President Donald Trump addresses the General Assembly at the U.N. headquarters in New York, U.S., September 21, 2017. REUTERS/Shannon Stapleton/File Photo

Trump slammed China’s efforts on North Korea, saying it had nothing to do with his failure to persuade Kim Jong Un to give up his nuclear weapons, but would stop because it was holding him hostage to China.

Xi said Washington, Washington, Washington, fighting the North Korean issue alone, did not understand China’s role in North Korea and should play a bigger role in forging a denuclearized Korea.

“As if the DPRK were a normal state, this is a must-win situation for the world,” Xi said at a working dinner for the U.N. on Friday night, using the acronym for North Korea.

“Since the visit of President Trump to Washington, there have been calls to internationalize the North Korean issue,” Xi said. “I wish to respectfully tell the United States that this would be a great mistake.”

He also condemned the U.S. decision to impose a new round of U.N. sanctions on North Korea, saying that the international community had to take a more positive stance.

On Saturday, Trump weighed in, accusing Xi of having “lied and cheated” and said China did nothing to help North Korea in the wake of the Nov. 29, 2017, nuclear test.

But there was little indication on Friday the United States would change course on North Korea, with White House spokeswoman Sarah Sanders saying it was Trump’s job to make sure Kim met his obligations.

On Tuesday, Tillerson, in his first speech to the annual General Assembly, said Washington could not allow North Korea to develop an intercontinental ballistic missile capable of striking anywhere in the United States. China is concerned the country could develop a nuclear-tipped missile capable of hitting the U.S. mainland.

North Korea on Saturday tested a new liquid-fueled intercontinental ballistic missile for the first time, which carries a much larger, longer-range warhead than its most recent missile, according to U.S. officials, prompting Tillerson to order an assessment.

U.S. intelligence officials believe North Korea would have the ability to reliably build an ICBM by the middle of next year, despite U.S. military exercises involving nuclear-armed bombers in South Korea.

Tillerson was also asked whether that would diminish its nuclear program, since developing ICBMs with a long-range nuclear warhead would mean the program had to shift to putting the warheads on shorter-range missiles, as had happened with previous ICBM launches.

The ICBM for Saturday’s test, a new intercontinental ballistic missile (ICBM), has an estimated range of around 5,500 km (3,410 miles), an official said, about 1,500 km longer than previous ones.

Xu Guangdong, China’s highest-ranking diplomat, said a successful test would underscore the country’s determination to maintain the nuclear deterrent for the sake of national security.