TOKYO (BLOOMBERG) - Top Japanese and American military officials affirmed a commitment to their joint security pact hours after a Bloomberg News report said United States President Donald Trump had privately mulled ending the longstanding treaty that has been a pillar of regional security.

Acting US Defence Secretary Mark Esper and Japanese Minister of Defence Takeshi Iwaya held talks over the phone on Tuesday and agreed to "work together to strengthen the Japan-US alliance", Japan's Defence Ministry said in a statement on Wednesday (June 26).

Officials in Tokyo said there were no plans to review the alliance and that they had received assurance from the White House about the pact's stability, after the report said Mr Trump recently mused to confidants about withdrawing from the treaty, his latest complaint about what he sees as unfair US security pacts.

Pentagon officials were not immediately available to comment on the Japanese statement, which also said that Mr Iwaya and Mr Esper agreed to work towards the complete, verifiable and irreversible denuclearisation of North Korea.

Mr Trump is due to arrive soon in Osaka, Japan, for the Group of 20 leaders summit that starts on Friday. The US leader will then travel to South Korea for a visit that is expected to provide a new push on nuclear disarmament talks with North Korea, which largely ground to a halt after the collapse of his February summit with the North's leader Kim Jong Un.

POST-WAR ALLIANCE

North Korea sees Japan as its sworn enemy and has threatened to use its nuclear arsenal to sink its neighbour into the sea. The US positions tens of thousands of troops in Japan, in part to deter North Korea.

Mr Trump sees the accord with Japan as too one-sided because it promises US aid if Japan is ever attacked, but doesn't oblige Japan's military to come to America's defence, according to three people familiar with the matter.

The treaty, signed more than 60 years ago, forms the foundation of the alliance between the countries that emerged from World War II.

Exiting the pact would jeopardise an alliance that has helped guarantee security in the Asia-Pacific, laying the foundation for the region's economic rise. Under the terms of its surrender in WWII, Japan agreed to a pacifist Constitution in which it renounced the right to wage war.