UK's new £3bn warship HMS Queen Elizabeth arrives in Portsmouth

Britain's biggest-ever warship has arrived at its base in Portsmouth for the first time.

Hundreds of people lined Portsmouth Harbour to welcome HMS Queen Elizabeth, an aircraft carrier which cost more than £3bn to build.

The 280m (918ft) vessel set sail in June from the Rosyth dockyard where it was built, and since then has been undergoing tests at sea.

Technically, it remains a civilian rather than a military ship until it is commissioned later this year.

It is also an aircraft carrier which does not yet have fixed-wing aircraft on board. F-35B Lightning II jets are still being built and tested in the US, and the ship won't be fully operational until 2020.

:: Navy's new flagship is a true feat of engineering

Theresa May, speaking on board, hailed the ship as a symbol of the UK as a "great global maritime nation".

The PM said: "Britain can be proud of this ship and what it represents.

"It sends a clear signal that as Britain forges a new, positive, confident role on the world stage in the years ahead we are determined to remain a fully engaged global power, working closely with our friends and allies around the
world."

"Whether the task be high intensity war-fighting, targeted action to fight terrorism, or humanitarian relief to save lives overseas, these ships will transform the UK's ability to project power around the world," she added.

Those on board and watching from the shore were treated to two separate flypasts of Royal Navy helicopters, the first featuring a Sea King, two Mk2 Merlins and two Mk3 Merlins, which were then joined by two Hawk jets for the second.

Defence Secretary Sir Michael Fallon said: "She is Britain's statement to the world: a demonstration of British military power and our commitment to a bigger global role.

"The thousands of people across the UK who have played a part in building her and her sister ship, HMS Prince of Wales, should be immensely proud as our future flagship enters Portsmouth."

The behemoth aircraft carrier sailed into the Solent before heading into Portsmouth, where, at its narrowest point, there was less than 20m (66ft) clearance on each side.

The band of the Royal Marines played as the ship slowly navigated into the harbour, which has had to be dredged to make room.

HMS Queen Elizabeth manoeuvred towards a new extended and reinforced jetty under her own power before tugs nudged her gently into position.

An 820ft (250m) exclusion zone, enforced by armed police in small boats, meant the port was effectively closed to the flotilla of boats that had turned out to greet the ship.

Lt Cdr Neil Twigg, a fast jet pilot responsible for integrating the F-35 fighter jet into the carrier group, said: "We are very ready, there is still a lot more work to be done, the aircraft is still going through its testing programme in America and the ship has still some more sea trials but we are on the right track."

Some members of the public, as well as politicians, have expressed concern over the £3bn price tag for the aircraft carrier.

But Admiral Chris Parry, a former senior Royal Navy officer, told Sky News that HMS Queen Elizabeth offers "real military power" to deter rogue states - as well as terrorist groups such as Islamic State.