(Bloomberg) -- Denuclearization is off the negotiating table with the U.S., North Korea’s ambassador to the United Nations said Saturday in a strongly-worded statement that also criticized EU member nations for playing “the role of pet dog” to Washington.

Ambassador Kim Song said that the “sustained and substantial dialogue” sought by the U.S. with Pyongyang was a trick done to suit its domestic political agenda, according the statement, which was first reported by Reuters.

“We do not need to have lengthy talks with the U.S. now and denuclearization is already gone out of the negotiating table,” Kim said.

The envoy’s letter comes at a sensitive time in U.S.-North Korea relations. Pyongyang may be preparing to conduct engine tests at a long-range rocket launch site to dial up pressure on President Donald Trump ahead of a year-end deadline it imposed to get a better deal from the U.S. in nuclear disarmament talks.

The U.S. has said it’s ready to engage in talks, but Saturday’s missive suggests Pyongyang is pulling away.

On Friday, the U.S. indicated it was withholding its support from hosting a human rights debate on North Korea next week, in what was seen as an effort to avoid antagonizing the North Koreans. U.S. allies, including Germany, France, Belgium and the U.K., have sought to hold such a meeting on Dec. 10, but would need U.S. backing to do so.

In his statement, Song referenced the Dec. 4 joint statement from six EU member states regarding North Korea as “yet another serious provocation.” He also defended tests of Pyongyang’s “super-large” multiple rocket launcher in November as necessary for self-defense.

“These countries often take issue with our self-defensive measures,” Song wrote. “We have never ever recognized such ‘resolution’ aimed at obliterating our sovereignty and the right to existence.”

As tensions rise, the warm relationship between Trump and North Korean leader Kim Jong Un -- who’ve met three times since 2018 -- has shown signs of strain.

Trump has revived his “Rocket Man” nickname for Kim as well as the threat of military force against North Korea. A North Korean official has again used the term “dotard,” or mentally weak old person, for the U.S. president.

(Updates with more detail from letter from first paragraph.)

To contact the reporters on this story: Chiara Vasarri in New York at cvasarri@bloomberg.net;David Wainer in New York at dwainer3@bloomberg.net

To contact the editors responsible for this story: Bill Faries at wfaries@bloomberg.net, Ros Krasny, Matthew G. Miller

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