The new base for the Royal Navy's next generation of warships is due to be unveiled.

Armed Forces Minister Adam Ingram will announce later on Tuesday which port will handle the state-of-the-art ships.

Six new surface warships are on order in a deal worth �4.3bn.

The first of the Type 45 destroyers is due to come into service this year.

A navy spokesman said: "In February this year the Ministry of Defence doubled the number of Type 45 destroyers it has on contract from an initial three ships to a �2bn order for six".

"Total cost of the six vessels when fully equipped is expected to be �4.3bn, making it the biggest single UK surface warship order for decades."

Defence spending

The warships are part of the government's commitment to a key defence programmes as outlined by Defence Secretary Geoff Hoon on Friday to MPs in the Commons.

Type 45 destroyers

Hulls hold extra equipment Hull design makes them harder for enemy radar to detect Ships hold 60 marines More than twice as many air defence missiles can be carried

Mr Hoon said this included plans to build 30 warships over the next 15 to 20 years making the new hardware the "envy of armed forces throughout the world".

This defence spending will include a pair of �10bn super ships with two "supercarriers" - twice the size of the Navy's existing carriers.

Each of the carriers will be able to carry 50 planes on board as they replace three existing carriers by 2012.

A Royal Navy spokesman said: "As the ships are expected to have a lifespan of up to 50 years, they are being designed with flexibility in mind to meet any changing demands."

The planes on board the ships are intended to be the American-designed Joint Strike Fighter.

Two amphibious assault ships HMS Albion and HMS Bulwark, which have been built at the BAE Systems shipyard in Barrow-in-Furness, will be affected by Tuesday's decision on the new home.

The spokesman said: "The 18,500-tonne vessels will replace HMS Fearless and HMS Intrepid, but will be substantially larger than the older, 12,200-tonne ships."