A call has been made for the planned new “national flagship” to be based in Portsmouth, next to the Royal Navy’s flagship HMS Queen Elizabeth.

The leader of Portsmouth City Council, Gerald Vernon-Jackson, has written to Prime Minister Boris Johnson calling for the successor for the Royal Yacht Britannia to be moored in the Hampshire city.

The Liberal Democrat said in his letter that Portsmouth Naval Base would be the best home for the vessel as it is closest to London and home to the Royal Navy and most of its fleet, including the aircraft carriers.

Mr Vernon-Jackson wrote: “The previous ship to perform this, and other duties, was HMS Britannia, which was based in Portsmouth for the whole of her career.

“Portsmouth is the home of the Royal Navy and this new ship will be a naval ship.

“The majority of the surface fleet is based in Portsmouth, including the flagship of the Royal Navy, HMS Queen Elizabeth.

“My understanding is that this new ship will be used by ministers, members of the royal family and leading industrialists to showcase the UK around the world.

“Of all the three naval bases in the UK, Portsmouth is the closest to London and therefore allows easier access for the people who will be using this new ship.

“For all of these reasons I am asking for an early decision to be taken that the new ship should follow in the footsteps of HMS Britannia and be home ported in HM Naval Base, Portsmouth.”

Last month, Defence Secretary Ben Wallace confirmed that the “floating embassy” could cost up to £250 million with the aim of it being completed as soon as 2024.

Labour has criticised the project for its “absolutely staggering” costs and said the money should be spent on tackling crime and anti-social behaviour.

The vessel will be the first national flagship since Britannia, which was decommissioned in 1997, but it will be a ship rather than a luxury yacht and is aimed at boosting the Prime Minister’s post-Brexit vision of the UK as a global trading nation.

The ship will be crewed by the Royal Navy and is expected to be in service for around 30 years.