(Bloomberg) -- The bonhomie between President Donald Trump and North Korean leader Kim Jong Un is nearing a key deadline showing new signs of strain.

Trump urged Kim over the weekend to “act quickly” to get a nuclear deal done, suggesting the two leaders could meet again “soon.” His comments came hours after North Korea ruled out nuclear talks without a policy change by the U.S. and reported on a military drill observed by Kim himself.

The two men who have what Pyongyang touts as “mysteriously wonderful chemistry” appear to be going in different directions as the clock ticks down. Kim has given Trump until the end of the year to ease up on sanctions or risk him taking a “new path,” meaning a possible escalation of military tensions during the U.S. presidential campaign.

North Korea’s foreign ministry turned up the heat further Sunday by criticizing U.S. efforts to highlight its human rights record in the United Nations. “Even if the DPRK-U.S. dialogue is held in the future, the nuclear issue would never be put under discussion before the withdrawal of the U.S. hostile policy would be put on the agenda for the sake of improved relations with the DPRK,” the state-run Korean Central News Agency quoted a ministry spokesman as saying.

The North Korean foreign ministry typically uses KCNA to issue its highest public pronouncements. On Sunday, it painted a bleak picture of the nuclear discussions, which have accomplished little since Trump and Kim agreed to “work toward complete denuclearization of the Korean Peninsula” in their first meeting in June 2018.

After more than a year of talks and three Trump-Kim meetings, the two sides remain divided on issues from sanctions relief to disarmament. Even though North Korea hasn’t taken any major steps to give up its weapons, Kim has won concessions from Trump that include canceling some U.S.-South Korean joint military drills that have drawn Pyongyang’s anger.

North Korea hasn’t explained what Kim intends to do on his “new path,” although the regime has often referred to his decision to halt tests of nuclear bombs and intercontinental ballistic missiles two years ago. In May, North Korea resumed tests of shorter-range ballistic missiles.

Kim may feel less pressure to cut a deal because he’s been successfully poking holes in the global web of sanctions against North Korea. Still Kim will be hard pressed to find a better U.S. negotiating partner than Trump, who shrugged off long-standing U.S. policy to meet with the North Korean leader in the first place.

“North Korea knows that the best way to approach the U.S. in an attempt for sanctions relief is to start from the top,” said Choi Soon-mi, a professor on North Korean studies at Ajou Institute of Unification.

That may explain why the regime launched a verbal attack on former Vice President Joe Biden, denouncing him as a “rabid dog” in a KCNA commentary last week. Biden has been critical of Trump’s North Korea policy and his personal praise for dictators.

Trump offered an unexpected response of his own on Twitter, mocking Biden as “sleepy and very slow,” but “somewhat better than” a rabid dog.

The North Korea warning about U.S. nuclear talks came despite the U.S.’s decision to suspend another round of military drills with South Korea. Defense Secretary Mark Esper said on the sidelines of a regional security conference that Washington and Seoul had “jointly decided to postpone this month’s combined flying training event” after “close consultation and careful consideration.”

Pyongyang last week blamed U.S.-South Korean military drills “as a main factor of screwing up tensions.”

--With assistance from David Wainer.

To contact the reporters on this story: Glen Carey in Bangkok at gcarey8@bloomberg.net;Jihye Lee in Seoul at jlee2352@bloomberg.net

To contact the editors responsible for this story: Brendan Scott at bscott66@bloomberg.net, Jon Herskovitz

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