U.S. President George W. Bush has again rejected direct talks with North Korea to negotiate an end to its nuclear arms program.

In making the announcement Thursday, White House spokesman Scott McClellan asserted that the direct negotiations approach didn't work previously.

John Kerry, Bush's presumptive rival in the November presidential elections, leveled charges Wednesday that Bush had failed in his North Korea policy.

Kerry wants to hold direct talks with Pyongyang on an array of issues, in addition to the nuclear question.

A North Korean foreign ministry spokesman said on Thursday that Pyongyang wants to discuss compensation for a possible freeze of its nuclear programs at a six-party working group meeting slated for May 12 in Beijing.