Differences over format have blocked talks for months with North Korea insisting on negotiating only with the United States and Washington insisting other countries be involved.

US President George W. Bush said he was "optimistic" about the proposed multilateral talks.

"We were very concerned about trying to enter into a bilateral agreement with Kim Jong Il because of the fact that he didn't tell the truth to previous administrations," he told reporters ushered into a cabinet meeting.

"So we took a new tack ... to engage China in the process so that there is more than one voice speaking to (North Korean leader) Mr. Kim Jong Il," Bush said, after Pyongyang signalled it was ready to join talks with the United States, China, Russia, South Korea and Japan.

"We are hopeful that Mr. Kim Jong-Il... will make a decision to totally dismantle his nuclear weapons program" in a verifiable manner.

"We're optimistic that that can happen."

A North Korean Foreign Ministry spokesman told the country's official news agency that the compromise proposal was offered Thursday in New York.

"At the recent DPRK (North Korea)-US talks, the DPRK put forward a new proposal to have six-party talks without going through the three-party talks and to have the DPRK-US bilateral talks there," the Korean Central News Agency quoted the spokesman as saying.

White House spokesman Scott McClellan told reporters that Washington used a third party to offer Pyongyang bilateral talks within a multilateral framework, but "in terms of the actual details and timing, these are still being worked out with our friends and allies."

Officials in Seoul said South Korea, Japan, the United States, Russia and China had been notified by Pyongyang that it accepted talks -- a breakthrough following months of stalemate.

Japanese leaders welcomed signs of North Korean flexibility, and the South Korean foreign ministry was pleased by the pay-off of months of tough diplomacy.

Moscow's Deputy Foreign Minister Yury Fedotov said the move "opens the way to a resolution" of the nuclear impasse.

The talks, likely to proceed in Beijing, could come as early as this month, according to one US official.

The United States hardened its tone Thursday when its top arms control official John Bolton warned Kim the days of blackmail were over and that Kim was "dead wrong to think that developing nuclear weapons will improve his security."

"The resolve that the (US, South Korean and Japanese) governments showed, all three of them, in telling the North Koreans through China ... that there wouldn't be substantive negotiations unless South Korea and Japan were in the room and at the table has paid off," Bolton added during a visit to Tokyo.

Pyongyang claims Washington is intent on launching an invasion to overthrow its communist regime, and has insisted that the United States first offer security guarantees to address the nuclear issue.

Bush has said Washington had no intention of attacking the Stalinist state and has promised significant US and international help once it scraps its nuclear weapons drive.

US officials have made frequent verbal attacks on North Korea: Bush added it to his "axis of evil" and as recently as this week Bolton said the lives of North Koreans under Kim were "hellish."

Bush has branded Pyongyang's demand for two-way talks on US demands that it cease developing nuclear weapons as "blackmail" and refused to offer a payoff for an end to the programs.

Any talks are certain to be tricky and any accord difficult to implement. It took nearly two years to negotiate a bilateral accord in 1994 that froze North Korea's previous nuclear weapons drive.

"When they sit down for talks, that is when the going gets tough," said Yu Suk-Ryul, North Korean expert at the government-affiliated Institute for Foreign Affairs and National Security here.

The nuclear crisis was triggered in October when Washington revealed that Pyongyang had broken the 1994 accord and was running a nuclear program based on enriched uranium.

Ratcheting up tension, North Korea kicked out UN nuclear inspectors late last year and then withdrew from the Nuclear Non-Proliferation Treaty. It has since claimed it has reprocessed 8,000 spent nuclear fuel rods after reopening its nuclear complex at Yongbyon, north of Pyongyang, frozen under the 1994 accord.

Washington believes North Korea extracted enough weapons-grade plutonium for about two nuclear bombs before it froze its Yongbyon plant. Reprocessing the fuel rods could provide enough additional material for around six bombs within months, according to analysts.

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