Foreign secretary Robin Cook has announced that Britain is to establish diplomatic relations with North Korea for the first time.

His statement came as the prime minister began a visit to South Korea to encourage trade and investment. Speaking in Seoul before the start of the Third Asia-Europe summit, Cook said that following the successful meeting the leaders of North and South Korea in June, the president of South Korea wanted other countries to engage with the north, to help accelerate peace relations between the two countries.

Cook commented: "If our action helps to take forward that process of reducing the tension between the two countries, then that will be a valuable and helpful step towards world peace."

He added that diplomatic relations with North Korea would also enable Britain lobby directly on issues of "deep concern", such as human rights.

The shadow foreign secretary, Francis Maude, has warned ministers that they should still deal catiously with North Korea. "North Korea's despotic regime treats its own people with contempt and has attempted to blackmail the world using the threat of nuclear weapons. Britain should continue to sup with a long spoon," he said.