SEOUL: North Korea accused South Korean President Lee Myung-Bak of driving his predecessor Roh Moo-Hyun to suicide.

Rodong Sinmun, official daily of the ruling communist party, angrily disputed criticism by the South's ruling Grand National Party over its timing of a nuclear test during the mourning period for Roh last week.

In a weekly radio speech on Monday, Lee also expressed regret that the North pushed through with the test when the South was grieving.

Roh threw himself off a clifftop on May 23 after being questioned in a corruption probe, sparking a national outpouring of grief.

North Korean leader Kim Jong-Il, who met Roh in a 2007 summit, on May 25 sent a message of condolences to his family.

But hours later the North carried out its second nuclear test, sparking condemnation by Seoul's news media and politicians of its apparent callousness.

'As to the mourning period mentioned by Lee, they themselves caused it (the death),' Rodong said in a commentary.

The paper said many South Koreans view the former president's death as nothing less than murder caused by a political vendetta.

'If the group of traitors (Lee's government) did not drive the former president to death through pressure, would there be this problem in the first place?' it said.

The paper urged Lee to confess his 'sins' and apologise to the people instead of trying to pick a fight with the North.

Supporters of Roh, who held office from 2003-8, accuse the conservative government of ordering a politically motivated probe into the former liberal leader. Prosecutors have denied such motives.

Rodong Sinmun also justified the communist state's nuclear drive.

'It is thanks to the bolstering of our self-defensive nuclear deterrence that peace has been maintained on the Korean peninsula, the most unstable flashpoint in the world,' the daily said.