Japan and Britain signed a bilateral defense cooperation agreement Wednesday aimed at facilitating joint military drills amid the increasingly severe security situation in the Indo-Pacific region due partly to China's growing military clout.

Japanese Prime Minister Fumio Kishida and his British counterpart Rishi Sunak held talks in London on the Reciprocal Access Agreement, which sets rules on the transportation of weapons during joint exercises or disaster relief operations in each other's countries.

Kishida's visit to the British capital was the third stop on his weeklong tour of Group of Seven countries in Europe and North America for talks with their leaders in the run-up to the group's summit in Hiroshima in May.

After the meeting, Kishida told reporters that Sunak, France's Emmanuel Macron and Italy's Giorgia Meloni had agreed to discuss nuclear disarmament and nonproliferation at the upcoming summit in the city devastated by a U.S. atomic bombing in 1945.

Japanese Prime Minister Fumio Kishida (L) and British Prime Minister Rishi Sunak shake hands after signing a bilateral defense cooperation agreement in London on Jan. 11, 2023. (Pool photo)(Kyodo)

Hailing the signing of the RAA, the Japanese prime minister said it "will elevate Japan-Britain security cooperation to a new high."

The British prime minister's office said in a statement the "landmark" defense pact, agreed in principle in May, will rapidly accelerate defense and security cooperation, and allow both Tokyo and London to deploy forces in one another's countries.

Japan signed such a treaty with Australia a year ago and the statement said Britain will be the first European country to have an RAA with the Asian nation, describing it as "the most important defense treaty" between Britain and Japan since 1902, when they signed the Anglo-Japanese Alliance.

"This Reciprocal Access Agreement is hugely significant for both our nations -- it cements our commitment to the Indo-Pacific and underlines our joint efforts to bolster economic security," Sunak said in the statement.

Japan and Britain will start respective domestic procedures necessary to implement the RAA as early as possible.

As part of efforts to boost security cooperation, the countries have also teamed up with Italy to develop a next-generation fighter jet by 2035.

During the meeting at the Tower of London, Kishida and Sunak agreed to arrange a so-called two-plus-two security meeting involving their foreign and defense ministers.

The two prime ministers also confirmed that they will promote negotiations for Britain's accession to a Pacific free trade pact, known as the Comprehensive and Progressive Agreement for Trans-Pacific Partnership.

Britain views Japan as a key East Asian ally in its "Indo-Pacific tilt," especially after its exit from the European Union in 2020.

With Japan holding the presidency of the G-7 this year, Kishida is paving the way for a successful summit by visiting its member nations that also include Canada and the United States, where he is scheduled to meet with Prime Minister Justin Trudeau and President Joe Biden, respectively.

Kishida, whose constituency is in Hiroshima, is hoping to promote his vision of a world without nuclear weapons at the G-7 summit, amid concern Russia may use a nuclear weapon in its invasion of Ukraine, launched last February.

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