A train flying North Korea flags and believed to be carrying leader Kim Jong Un was seen by AFP journalists approaching Beijing Railway Station on Tuesday, ahead of a massive military parade on Wednesday.

Kim will join Chinese President Xi Jinping, Russia's Vladimir Putin and two dozen other leaders at the huge spectacle to mark 80 years since the end of World War II.

China will showcase its military prowess with troops marching in formation, flypasts and other high-tech fighting gear at the showpiece extravaganza centred on Beijing's Tiananmen Square.

South Korea's Yonhap news agency, which early on Tuesday said Kim's train had crossed into China, also reported the special armoured train's arrival in the capital.

It is only Kim's second reported trip abroad in six years.

China has to

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