'Trump asks Tokyo for $8 bn to keep US troop in Japan'

US President Donald Trump has asked Japan to quadruple its payments for US forces stationed there, Foreign Policy reported, citing unnamed current and former US officials, as Washington presses long-standing allies to increase their defence spending.

Washington wants Tokyo to increase annual payments for the 54,000 US troops in Japan to around $8 billion from about $2 billion, Foreign Policy said, citing three unnamed former defence officials. The current agreement expires in March 2021.

The demand was made to Japanese officials during a trip to the region in July by John Bolton, at that time Trump's national security adviser, and Matt Pottinger, who was then the Asia director for the National Security Council, Foreign Policy said.

A spokesman for the Japanese foreign ministry said the report by the US global affairs publication is incorrect and no U.S.-Japan negotiations on a new agreement have taken place.

Representatives of the US government were not immediately available to comment outside of business hours.

Many US allies are coming under pressure on defence spending from Washington.

Trump has also insisted Seoul shoulder more of the cost of the US military presence in South Korea, where it serves as deterrence against North Korea, and has floated the idea of pulling U.S. troops from the peninsula, Reuters reported on Wednesday.