Britain will sign a new 50-year bilateral security treaty with Australia.

The Aukus-related agreement will be ratified whilst David Lammy, the Foreign Secretary, and John Healey, the Defence Secretary, visit the country.

The pair met their counterparts and Australian Prime Minister Anthony Albanese at the annual Australia-UK ministerial meeting, or Aukmin, in Sydney on Friday.

Mr Lammy and Mr Healey will travel to Melbourne on Saturday to meet businesses involved in the Aukus submarine programme. They will also visit Darwin as the Carrier Strike Group docks in the Northern Territory.