SEOUL - North Korea Thursday accused the South of escalating tensions on the Korean peninsula to the brink of war.

Rodong Sinmun, the official daily of the North's ruling communist party, said the United States and its allies had launched a smear campaign against Pyongyang at the UN Security Council and drastically raised the danger of invading the North.

"The situation on the Korean peninsula is more tense than ever," the daily said.

The UN Security Council last week adopted tougher sanctions against North Korea over its defiant pursuit of its missile and nuclear programmes.

Rodong Sinmun said the Security Council's "vicious smear campaign" against Pyongyang had breached the country's sovereign rights and drastically raised the danger of an invasion of the North.

It accused South Korean "warmongers" of triggering "war hysteria" by publicising war games exercises through the media in order to divert public attention away from their policy failures.

"This is an open threat to the DPRK (North Korea) and a dangerous move to push the situation to the brink of a war by escalating tension," the daily said.

It accused the South of being "keen on moves for aggravating tension and igniting a war of aggression against the North with bloodshot eyes."

These moves go against "the desire and demand of all the fellow countrymen for peace and reunification of the country," it said, warning the conservative government of President Lee Myung-Bak would have to "pay dearly for its crimes."

North Korea last week vowed to build more nuclear bombs and start enriching uranium for a new atomic weapons programme, in response to the new UN sanctions.

US President Barack Obama warned Wednesday that a nuclear-armed North Korea was a "grave threat" and said he would not tolerate the Stalinist state's provocative strategy of extracting rewards with belligerent behaviour.

Following a summit with the South Korean president in Washington, Obama also vowed to defend South Korea with the US nuclear umbrella and said Washington planned "serious enforcement" of sanctions against the North.

Lee vowed Wednesday never to accept a nuclear-armed North Korea, while saying he hoped for an eventual reunification of the divided peninsula.