The UK Royal Navy (RN) has commissioned its fifth of seven Astute-class nuclear attack submarines, HMS Anson, at BAE Systems’ shipyard in Cumbria, England.

The event was attended by British Prime Minister Boris Johnson, Defence Secretary Ben Wallace, Australian Deputy Prime Minister Richard Marles and submarine’s sponsor Julie Weale.

The submarine will remain in Barrow for some more weeks to undergo final assessments.

After completing the tests and receiving required tweaks in its systems, HMS Anson will depart to its homeport, HM Naval Base Clyde, in Faslane to prepare for sea trials.

Christened in 2020, Anson has been built with an investment of £1.3bn. It took more than 11 years for building the vessel and involvement of around 10,000 people from 400 firms across the country.

It is powered by a Rolls-Royce nuclear reactor, which will allow submarine to remain operational for 25 years without refuelling.

At the commissioning event, Johnson and Wallace also revealed that the Royal Australian Navy’s (RAN) crews will receive training aboard this RN’s newly commissioned Astute-class submarine.

This training is part of the AUKUS trilateral security pact, formed between governments of Australia, the UK and the US.

Johnson said: “From the Pacific Ocean to the Baltic Sea, our submarine service is protecting UK and our allies 24 hours a day, seven days a week, and deployment of Australian submariners alongside our British crews epitomises strength of AUKUS partnership.”

The effort is intended to strengthen defence ties and promote stability in the Indo-Pacific region.

Marles said: “Today’s announcement of Australian submariners training aboard HMS Anson says everything about our future plans of building the AUKUS partnership.

“The technology, capability and lethality on show is truly impressive and Australia looks forward to progressing our talks through AUKUS partnership.”