John Negroponte's first mission as US deputy secretary of state is expected to take him to Asia next week to shore up last week's breakthrough deal with North Korea, under which Pyongyang is to close its nuclear bomb-making facilities in return for aid and peace talks.

Mr Negroponte, the former national director of intelligence who took up his new post only last week, would visit China, South Korea and Japan, officials said. One senior official said Mr Negroponte planned to add Pyongyang to his itinerary, though others either denied this or said such a trip was unlikely at this stage. The US State Department said only: "We have nothing to announce at this time."