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Japan and US on biggest ever military manoeuvres

3 December 2010 Last updated at 12:59 GMT

Japan and the United States are carrying out their biggest joint military exercises - marking 50 years of alliance.

The drill was planned before North Korea's recent shelling of an Island belonging to South Korea, but it is taking place just days after an American-South Korean show of force which is designed to put pressure on the North.

The BBC's Roland Buerk reports from Tokyo.