Japan and the UK are set to sign a major defense pact in December that will allow the countries to boost cooperation with the US in the Indo-Pacific and bolster defenses against a growing threat from China.

The countries will sign a mutual access agreement (RAA), according to two people familiar with the talks. It would follow a similar agreement Japan signed with Australia in January and is another sign that Tokyo is deepening defense ties with allies and partners to prepare for the possibility of war with China over Taiwan.

The agreement will facilitate joint exercises and logistical cooperation between the nations. It would also set up a legal framework to ease cumbersome bureaucratic red tape for troop access to each other’s countries.

“A mutual access agreement between Japan and the UK will make it easier for both sides to exercise and operate together, allowing British armed forces to more easily deploy and train in the Indo-Pacific region,” said Asia’s Zach Cooper. A security expert at the American Enterprise Institute think tank.

“For decades, alliances in Asia have been held together by the US in what has been described as a hub-and-spoke model. Now some US allies, including Japan, the UK and Australia, are acting as hubs themselves.

The nations agreed to open talks on the RAA in May when Prime Minister Fumio Kishida met his then-UK counterpart Boris Johnson in London.

The agreement will be another example of strengthening ties between Japan and Britain. In December, the two countries are expected to unveil details of the partnership to co-develop their next fighter jet.

Cooper added, “This is a reaction to increasing pressure from China, but also to growing concerns about the credibility of the United States.”

While President Joe Biden revived the U.S. alliance, Japan became nervous during the previous administration when then-President Donald Trump threatened to withdraw U.S. troops from Japan on several occasions.

Christopher Johnstone, a former Pentagon official, said the RAA would be a “significant step forward” and highlight Japan’s efforts to diversify security ties with US allies and partners. But he said the practical impact would be less because Japan has less military interaction with the UK than Australia.

Japan is also in the preliminary stages of considering a similar agreement with the Philippines, which Johnstone said would be more significant.

“The RAA between Japan and the Philippines would be more strategically effective,” said Johnstone, who is now at the CSIS think-tank. “Negotiations may take time, but the prospect of deeper defense cooperation between Tokyo and Manila will send a message to China that the web of US alliances in the region is deepening.”

The US is trying to increase access to bases in the Philippines, which would be a strategically important location in the event of a war on Taiwan.

US military officials welcome Japan’s push to sign mutual access agreements because they make it easier for Japanese and American allies to conduct joint training and exercises and ease efforts to overcome logistical obstacles. Washington wants to increase military cooperation and interoperability with allies in ways that could prove critical in the event of a war with China.

Over the past two years, the US and Japan have stepped up efforts to prepare for a potential conflict with China over Taiwan, including serious war games and more regular joint military exercises.

Japan is in advanced talks with the U.S. to acquire Tomahawk cruise missiles that could attack targets in eastern China, according to people familiar with the discussions.

In a statement after a meeting between US Secretary of State Antony Blinken and Japanese Foreign Minister Yoshimasa Hayashi in Germany on Thursday, the State Department said the two diplomats discussed “the need to maintain peace and stability across the Taiwan Strait”.

Separately, top White House officials held sensitive talks in London in April about what role the UK could play in the event of a conflict over Taiwan.

People familiar with the UK-Japan RAA talks cautioned that a final agreement on the deal and cooperation on fighter jets depended on political developments in the UK, where Rishi Sunak recently became the third prime minister in two months.

The Japanese Prime Minister’s Office referred inquiries to the Defense Ministry, which could not be reached for comment. A UK Ministry of Defense spokesman said talks were “making positive progress” but it would be “inappropriate” to comment on the signing of the RAA at this time.

Additional reporting by John Paul Rathbone

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