Japan’s prime minister is set to arrive in Australia to strengthen ties with one of her country’s strongest allies as she seeks to build on an updated regional strategy laid out in Vietnam.

Prime Minister Sanae Takaichi is scheduled to touch down late on Sunday local time in Canberra for the three-day visit, which will focus on defence, critical minerals and broader economic security. The two countries have grown increasingly concerned about the changing security and economic environment in the region, with Japan taking a more assertive military stance and looking to build economic ties and stable supply chains with nations such as Vietnam.

With US focus shifting elsewhere and China growing stronger in the Asia-Pacific region, the two nations’ militaries are holding frequent joint exercises and are now looking to share technology – including Australia’s decision to purchase Japanese naval vessels. The multibillion-dollar deal, which Japan sees as the potential foundation of exports to nations such as New Zealand or India, is one symbol of the relationship and shows how Japan’s defence posture has shifted in the past 10 years.

The security environment in the Asia-Pacific region is “increasingly severe,” Shinjiro Koizumi, Japan’s defence minister, said last month. “We will pursue multilayered cooperation between Japan and Australia with an open mindset, not only in frigates, but also in areas such as unstaffed systems, cyber and space, as well as joint production of defence equipment,” he said while standing on the front deck of a Japanese warship in Melbourne.

“As uncertainty in our surrounding security environment continues to grow, the need for Japan and Australia to work together and pool our wisdom to contribute to regional peace and stability is greater than it has been at any point in the past 50 years,” Koizumi said.

Koizumi will be in the Philippines this week to observe an exercise in which armed Japanese troops will participate for the first time since World War II, along with the Australian and US militaries. Tokyo will deploy 1,400 troops to join combat drills for the first time, with its navy using a missile to help sink a ship.

As well as tight defence ties, Takaichi’s visit will emphasise the close economic relationship, with Australia a critical supplier of energy, iron ore, food and other commodities, and Japanese firms now the second largest investors in Australia.