US marines take position in the smoke during a joint landing exercise between the US and South Korea in the southeastern port city of Pohang on November 4, 2009. South Korea and the US staged a military landing exercise amid the heightened tension over North Korea's nuclear programme. North Korea announced on November 3, it has produced more plutonium for its atomic weapons programme, putting further pressure on the United States to start direct talks. Getty Images logo Getty Images 1 month ago

US marines take position in the smoke during a joint landing exercise between the US and South Korea in the southeastern port city of Pohang on November 4, 2009. South Korea and the US staged a military landing exercise amid the heightened tension over North Korea's nuclear programme. North Korea announced on November 3, it has produced more plutonium for its atomic weapons programme, putting further pressure on the United States to start direct talks.