HMS Queen Elizabeth, the largest warship ever built for the Royal Navy, has begun her maiden voyage.

The 65,000-tonne aircraft carrier sailed out of Rosyth dockyard on the Firth of Forth earlier this week and is now undergoing sea trials off Scotland's coast.

She is being escorted by two smaller warships and submarine-hunting helicopters.

The 920ft-long vessel, which cost more than £3 billion to build, is set to become the Royal Navy's flagship vessel.

Andrew Canale, commanding officer of the escort frigate HMS Sutherland, said: "It is a huge honour for us all to be the first ship to escort HMS Queen Elizabeth on her maiden sea voyage.

"This is a new chapter in the history of the Royal Navy in which our aircraft carriers will have the ability to project power globally for the next 50 years.

"Everyone in HMS Sutherland is proud to be involved in this historic occasion. For me and all my ship's company, seeing her on the ocean waves for the first time is a sight we will never forget."

The sea trials will test the Queen Elizabeth's engines and her ability to produce fresh water.

During her launch on Monday the 230ft-wide warship cleared the barriers at Rosyth with a gap of just 14 inches on either side.

The carrier was then guided under the Forth's three bridges by 11 tugs at a speed of around 8mph.

More than 10,000 people were involved in the launch, the Royal Navy said.