The Queen has marked the Duke of Edinburgh's 90th birthday by making him the Lord High Admiral of the Navy.

Her Majesty has held the office of the titular head of the Navy since 1964 but passed it on to her husband as he celebrated his ninth decade.

The office of the Lord High Admiral dates from the 14th century.

Observers say the Prince Consort had a bright future in the Royal Navy and he would have been First Sea Lord.

But the Duke's flourishing naval career came to a premature end in 1951 when he married the then Princess Elizabeth.

The health of his father-in-law George VI was deteriorating and the Queen-in-waiting was required to take on more royal responsibilities.

He has spoken of his fascination with the sea describing it as "an extraordinary master or mistress".

Although he gave up his career, the Duke has remained closely associated with service life.