According to The Daily Telegraph, Britain’s largest ever warship is due to squeeze out of its dockyard for the first time as early as Monday afternoon, as the ship heads out on sea trials.

The 65,000 ton HMS Queen Elizabeth (R08) is expected to slip out of Rosyth dockyard and into open water through an exit with only 14-inch/35.5-cm clearance on either side and 20 inches/50.8 cm of water under the keel.

The aircraft carrier will then edge along the Forth under three bridges, including the landmark rail bridge, with a little over six feet to spare.

The trials mark the latest milestone in the nearly decade-long building of the Royal Navy’s two carriers, at a cost of more than £6bn. The Navy is also preparing for the warship’s first appearance to attract a concerted Russian spying effort, with submarines, ships and planes try to get a good look at the UK’s new flagship.

A Royal Navy warship is expected to escort HMS Queen Elizabeth (R08), while shore-based helicopters look out for submarines as commanders try out the warship in the North Sea and Moray Firth.

Commander Fiona Percival, head of logistics on the ship said: «The Russians will come and look, but they look at everything».

Commander Mark Deller, commander air, said the ship would be accompanied by a frigate or destroyer.

He said: «We will go where it’s best to go and not where it’s best for a Soviet nuclear to go, so the reality is we can probably look after ourselves as long as our escort is in the right place at the right time. You don’t have to hang around and endure it, you can move away and go somewhere else».

Sailors and engineers have worked round the clock getting the vessel ready. A total of 1,000 sailors and contractors will be onboard for the first six weeks of testing. Crew have spent hours each day carrying out safety drills for fires, flooding and personnel overboard. More than 650 doors and hatches have been checked to ensure they are watertight and fire safe.