North Korea reaffirmed its decision to break off negotiations on its nuclear weapons programme during a visit to Pyongyang by Russian Foreign Minister Sergei Lavrov, dpa quoted the North Korean news agency KCNA reported today. The statement came as US President Barack Obama and Japanese Premier Taro Aso agreed to push for an early resumption of the so- called six-party talks. The Russian delegation noted North Korea's stance that "there is no need to hold the six-party talks any longer," it reported, quoting a Foreign Ministry spokesman in Pyongyang. Lavrov said on Thursday he was sceptical about an early resumption of the six-party talks involving the two Koreas, China, the US, Japan and Russia. He added that an early breakthrough could not be expected, the Russian news agency RIA Novosti reported. North Korea withdrew from the nuclear talks in reaction to criticism from the UN Security Council to the country's controversial rocket launch on April 5. It also threatened expand its nuclear deterrent and to restart the operation of nuclear installations capable of producing weapons-grade materials. Lavrov was the first high-ranking representative of a foreign government to visit North Korea since the rocket test. Meanwhile, despite North Korea's decision to end the negotiations, Japan and the US have agreed to seek an early resumption of international talks on ending North Korea's nuclear weapons programmes, Japan's top government spokesman said Friday. Japanese Premier Taro Aso and US President Barack Obama in a 15- minute telephone conversation Friday agreed to strengthen bilateral cooperation in dealing with North Korea's missile issues as well as non-proliferation of nuclear weapons. Obama and Aso also agreed on the importance of a united voice in the wake of North Korea's rocket launch. On nuclear disarmament, Aso told Obama that he supports a comprehensive review of Washington's nuclear policy based on an Obama speech delivered in Prague earlier this month, which called for a world without nuclear weapons.