With South Korean President Yoon Suk-yeol set to meet leaders of the United States and Japan Wednesday during a North Atlantic Treaty Organization (NATO) summit in the Spanish capital of Madrid, North Korea has accused the US of setting up a NATO-like military alliance in Asia with an objective to oust its government. North Korea said this has compelled it to develop stronger defences, news agency Reuters reported.


"While blatantly holding joint military exercises with Japan and South Korea, the United States is making a full-fledged move to establish an Asia-style NATO," the foreign ministry of North Korea said in a statement on its website Sunday, the report said.


The statement comes at a time there are concerns North Korea could be preparing its first nuclear test in five years, and after South Korean President Yoon Suk-yeol and US President Joe Biden signed an agreement to deploy more US weapons if required to deter the North.


Yoon Suk-yeol, meanwhile, will be the first South Korean leader to attend a NATO summit, and he plans to drum up international cooperation against North Korea's nuclear programme, Reuters had earlier reported, quoting the presidential office.


South Korea is said to be aiming to strengthen its partnership with NATO, and play a bigger global security role. The country’s national security adviser said last week South Korea plans to set up a delegation to NATO’s Brussels headquarters.


The NATO Summit will take place on June 29 and June 30, and Yoon has been invited as the organisation's Asia-Pacific partner. He left for Spain Monday.


North Korea Vows 'Even Stronger' Defence


Meanwhile, the military forces of the US, South Korea and Japan recently conducted joint exercises conducted, and the US-South Korea exercises also involved an American-made aircraft carrier for the first time in more than four years.


While North Korea has itself conducted several missile tests this year, the foreign ministry statement said the joint drills by the US, South Korea and Japan were being organised in preparation for a war aiming to overthrow it, the Reuters report said.


"This proves the hypocrisy of the U.S. rhetoric of 'diplomatic engagement' and 'dialogue without preconditions', while at the same time revealing again that there is no change in the U.S. ambition to overthrow our system by force," the ministry was quoted as saying in the statement.


It also reportedly said the US hostility forced North Korea to strengthen its defences further, without elaborating on the efforts or referring to its nuclear programmes.


"The reality ... makes us feel the need to make all-out efforts to develop even stronger power to be able to subdue all kinds of hostile acts by the United States," the statement read.


The US has been insisting that North Korea give up its nuclear weapons, and has offered many times to meet North Korean officials "at any time without preconditions" to discuss the matter. North Korea has dismissed the offers.