Japan's cooperation is being considered in a trilateral security pact covering the Indo-Pacific region.

The defense chiefs of the United States, Britain and Australia say they are considering working with Tokyo on advanced technology projects. It would come under the security framework, known as AUKUS.

In a joint statement released on Monday, the three defense chiefs said AUKUS recognizes "Japan's strengths and its close bilateral defense partnerships with all three countries."

One of AUKUS's so-called pillars calls for cooperation on sophisticated technologies, including hypersonic missiles and artificial intelligence.

The administration of US President Joe Biden has been seeking the increased participation of allies and like-minded nations.

A senior US official says the matter will likely be discussed when Biden meets Prime Minister Kishida Fumio in Washington on Wednesday.

Japanese Defense Minister Kihara Minoru said: "It is important for the peace and stability of the Indo-Pacific region to strengthen defense cooperation between the United States, Britain and Australia by promoting AUKUS ties. Japan will steadfastly support these efforts."

Meanwhile, Australia's prime minister has made it clear that there are no plans to add a fourth member to the pact. Anthony Albanese said: "What's proposed is to look at Pillar Two of AUKUS, and look at, project by project, whether there would be engagement, and Japan is a natural candidate for that to occur. What is not proposed is to expand the membership of AUKUS."

Analysts say Australia might be cautious as it considers Japan's security measures vulnerable to cyberattacks and espionage.