The crew lined the decks as Invincible arrived in port

The refit, at Rosyth, has taken 18 months to complete and cost �65m.

Hundreds of well-wishers and friends and family crowded Portsmouth's round tower as the warship arrived at the naval base on Friday morning.

Her captain, Trevor Soar, said the refit had made the Invincible "state of the art".

We are now finishing our sea trials and training and are due to replace Ark Royal as the fleet flagship later this year Captain, Trevor Soar

"It's given us a new operations room which will allow us to fight much more effectively.

"Really what we've done is bring the ship up to the state of the art - now we'll be able to operate the latest navy helicopter, the Merlin.

"We are now finishing our sea trials and training and are due to replace Ark Royal as the fleet flagship later this year."

The Invincible was launched on 3 May 1977, serving in the Falklands in 1982.

Most recently she served in the Gulf enforcing the no-fly zone over Iraq and also operated in the Balkans during the Kosovo crisis.