North Korean leader Kim promises to advance his nuclear program and criticizes the U.S.-South Korea-Japan partnership.

According to state media on Sunday, North Korean leader Kim Jong Un declared that his nation is seriously threatened by the United States’ strengthened security alliance with South Korea and Japan and promised to strengthen his nuclear weapons program even more.

Although Kim has issued similar warnings in the past, his most recent remarks suggest that the North Korean leader is unlikely to accept President Donald Trump’s invitation to meet and resume diplomatic relations anytime soon.

Kim said the U.S.-Japan-South Korea trilateral security partnership, which was formed as part of a U.S. plot to create a regional military bloc akin to NATO, is inviting military imbalance on the Korean Peninsula and “raising a grave challenge to the security environment of our state” in a speech commemorating the 77th founding anniversary of the Korean People’s Army on Saturday.

He reiterated the unwavering policy of further developing the nuclear forces, KCNA said, referring to a number of new plans for quickly bolstering all forms of deterrence, including nuclear forces.

Kim has concentrated on expanding and updating his nuclear weapons stockpile in the face of stalled diplomatic relations with the United States and South Korea in recent years. As a result, Japan is now a part of more trilateral training and bilateral military drills between the US and South Korea. North Korea has reacted negatively to those exercises, accusing them of being invasion rehearsals.

Trump boasted of his high-stakes summit with Kim during his first term and has since declared he would reach out to him again since his inauguration on January 20.

At a joint press conference with Prime Minister of Japan Shigeru Ishiba on Friday, Trump said that “We will have relations with North Korea, with Kim Jong Un. I got along with him very well, as you know. I think I stopped the war.