The ship's bow and stern are still on site

The major excavation of Henry VIII's 15th Century warship is a clear-up operation prior to a full archaeological and environmental survey.

The dives, which began on Tuesday, were commissioned by the Ministry of Defence.

The move comes after the Royal Navy revealed �200m will spent on regenerating Portsmouth so it can house the next generation of warships, including the new aircraft carriers.

However, the route to the naval base is not shallow enough for the new super-carriers - which are twice the size of existing aircraft vessels.

New approach to be dredged

The Navy's preferred route crosses the wreck site of the Mary Rose, a couple of miles out into the Solent from the harbour mouth.

John Lippiett, chief executive of the Mary Rose Trust, said the operation would enable them to excavate important parts of the ship which have remained buried since the raising of the hull in 1982.

He said: "These are very exciting times indeed for the Mary Rose. This is the most thorough examination by divers of the wreck site since 1982."

EXCAVATION PROGRAMME Clear the site of rubbish and debris left behind by the original excavation team Excavate items that had to be left buried at the wreck site Find other items and even sections of the ship

Mr Lippett added: "We don't want to raise expectations too high but, at the same time, it's the excitement of the unknown that is spurring us on."

Ian Oxley, head of maritime archaeology at English Heritage, praised the MoD for carrying out the survey.

He said: "It is the same as a survey on land when a motorway or a runway is being built. The MoD is recognising the possible impact their plans could have."