In a statement issued last week, the top diplomats of Canada, France, Germany, Italy, Japan, Britain, the United States and the European Union reiterated their longstanding call for the "complete denuclearisation of the Korean Peninsula".

The G7 foreign ministers also demanded that Pyongyang abandon its nuclear weapons, and strongly condemned recent arms transfers from North Korea to Russia, asking the two countries to "immediately cease all such activities".

North Korea last year declared itself an "irreversible" nuclear power and has repeatedly said it will never give up its nuclear programme, which the regime views as essential for its survival.

Jo Chol Su, a high-ranking official at Pyongyang's foreign ministry, said he "resolutely" rejects and "most strongly" condemns the recent G7 statement, calling it "groundless".

He said members of the G7, especially the United States, have "disgraceful records by doing considerable harm to international peace and security", and that the group "has lost the justification for its existence".

The "G7, the remnant of the Cold War, should be dismantled immediately," Jo said, according to Pyongyang's state-run Korean Central News Agency.

He accused the group of being a "peace strangler, confrontation maniac and nuclear war merchant".

Historic allies Russia and North Korea are both under international sanctions -- the former for its invasion of Ukraine and the latter for its nuclear weapons and missile programmes.

Their growing military cooperation has been a source of concern for Ukraine and its allies, especially following North Korean leader Kim Jong Un's summit with Russian President Vladimir Putin in September.

Using the North's official name, Pyongyang said Saturday that "no matter what others may say, the friendly and cooperative relations between the DPRK and Russia aspiring after independence, peace and friendship will steadily grow stronger".

On Monday, US and South Korean defence chiefs updated for the first time in a decade a key military agreement to counter Pyongyang, part of the allies' effort to ramp up defence cooperation in the face of the North's growing nuclear threats.