The UK leader’s talks in Seoul are expected to tackle the stalemate over Pyongyang’s weapon's ambitions and British business interests in the region.
He is also expected to reaffirm the need to hold multilateral talks on the nuclear crisis.
The prime minister was scheduled to leave for Beijing later on Sunday.
Blair’s Asia tour began in Japan where he discussed with his Japanese counterpart, Junichiro Koizumi, Pyongyang’s nuclear programme and measures to rebuild post-war Iraq.
Blair’s visit to South Korea came a day after US officials accused North Korea of building a second secret facility for producing weapons-grade plutonium to help it enlarge its nuclear arsenal.
The North Korean News Agency (KCNA) reiterated the country's concerns over US military plans in the peninsula.
Blair is on the second leg of his East Asia tour that has been overshadowed by the death in Britain of Dr David Kelly, who was a ministry of defence consultant on Iraq’s weapons.
The prime minister said he would not recall parliament to debate Kelly’s death, which police said was the result of the suicide.
Blair said a judicial inquiry looking into the death should be allowed to run its course.
“I think… recalling parliament would generate more heat than light,” he said in an interview with Sky News, recorded in Japan.
“I don’t think it would be appropriate,” he said.
Kelly was believed to be the unnamed intelligence official who had told BBC in May that the British government had manipulated a dossier on Iraq’s alleged weapons of mass destruction, to gain public support for the war.
The government announced an “urgent” inquiry on Saturday to investigate the circumstances that led to the apparent suicide of Kelly.
The scientist’s death has caused the worst crisis of Blair’s political career.