TOKYO (AFP) - Japan gave its military the green light on Friday to shoot down any incoming North Korean rocket, with tensions high ahead of a planned launch that the US and allies say will be an illegal missile test. Japanese and US warships have already deployed ahead of the April 4-8 window, when the secretive North has said it will launch a communications satellite - warning that shooting it down would be seen as an act of war. But South Korea, Japan and the United States have all warned the North that any launch would be unacceptable, amid fears the regime is actually intending to test a long-range missile that could reach North America. Russia - which with the two Koreas, China, Japan and the US is part of a six-party forum working on the North's nuclear disarmament - urged Pyongyang not to carry out the launch, saying there was no need to "ignite passions". The security council in Japan, officially pacifist since the end of World War II, decided ahead of time to shoot down any incoming missile that could hit its territory rather than wait until a launch. "The security council this morning decided to issue a destruction order in advance," said Defence Minister Yasukazu Hamada. "We will do our best to handle any flying object from North Korea." Japan later began relocating its Patriot missile defence batteries ahead of the expected rocket launch, local media reported. The North said Thursday that even referring a launch to the United Nations would ruin the long-running and erratic six-nation nuclear disarmament talks, during which North Korea has already tested one missile and an atomic bomb. US National Intelligence Director Dennis Blair said the North wanted to show it had the technology to launch an intercontinental ballistic missile. The North is believed to be preparing to test a Taepodong-2 that could hit Alaska. "North Korea is attempting to demonstrate an ICBM capability through a space launch," Blair said. Japan has announced no plans to strike the North Korean rocket unless it appears to pose a direct threat, for example due to a mishap that could send an errant missile or debris flying toward the country. "There are various scenarios - for example, a case of failure," Hamada said. "It's extremely unpleasant that an object flies over our territories." Pyongyang has reportedly already put a rocket onto one of its launch pads, raising the stakes in a delicate diplomatic stand-off that has come just two months into the new US administration of President Barack Obama. Enigmatic North Korean leader Kim Jong-Il reportedly suffered a stroke in August, and some analysts speculate he is trying to demonstrate he remains firmly in control of the country. Though a recent photo showed him looking thin, the North's official media have reported more than three times as many public appearances by Kim so far this year than over the same period in the previous year. The six-nation talks have offered the North aid and security guarantees in exchange for dismantling its nuclear programme. North Korea said Thursday that bringing any launch to the United Nations would be a "hostile action" that would end the negotiations. The United States, which says the launch would violate a UN Security Council resolution, has vowed to do so. "The six-party talks will become non-existent," a spokesman for the North's foreign ministry told official media. In Moscow, Russian Deputy Foreign Minister Alexei Borodavkin told reporters: "North Korea would be better off refraining from it." "There is no need to ignite passions around this problem," he was quoted as saying by Russian news agencies. "All the issues that arise in connection with the planned launch one way or another need to be decided by way of dialogue and consultations." Senior US, Japanese and South Korean negotiators were to meet in Washington later Friday to discuss the situation. Japan's order for a shoot-down is the first since the nation revised its defence law in 2005. Asked whether Japan was capable of such an intercept, Hamada said: "We have obviously prepared to be able to do it. I have no doubt we can do it."