BEIJING, Feb 25: US and North Korean envoys staked out widely divergent positions at six-party talks on the crisis over the North's nuclear arms programmes on Wednesday.

But host China said there had been some consensus among the participants by the end of the day, although differences remained. One Chinese official described the atmosphere of the talks as pragmatic, sincere and frank.

And Japan warned North Korea it could not expect economic aid from its cash-rich neighbour without solving rows over both its nuclear threat and its kidnapping of Japanese nationals.

Tokyo's position was reaffirmed in a keynote speech by Japanese envoy Mitoji Yabunaka at the opening session of the talks. The United States and the North, the two protagonists in the 16-month-old impasse, held an hour of informal talks in the afternoon. It was not clear if this covered both Pyongyang's declared plutonium programme and the suspected uranium enrichment that it denies.

After half a year of shuttle diplomacy, delegates from the two Koreas, the United States, China, Russia and Japan kicked off the talks with a group handshake before taking their places at a hexagonal table in a state guest house for the second such meeting brokered by China.

South Korea proposed six-way talks be held every other month, with working group meetings in between, its chief negotiator, Lee Soo-hyuck, told reporters after the talks.

It also put forward a three-phase plan that would be the basis for Thursday's discussions, he said. The talks are expected to finish on Friday but could be extended, officials have said.

Under the South's plan, the North would pledge its intention to dismantle its nuclear programmes and other countries would meet its security concerns. The second phase would be implementation and the third would address other issues.

US Assistant Secretary of State James Kelly insisted on the irreversible, verifiable dismantling of all North Korea's atomic arms programmes, but said Washington did not intend to attack the country it branded part of an "axis of evil" with Iran and pre-war Iraq. -Reuters