The Queen's eldest grandson, Peter Phillips has married his Canadian bride, Autumn Kelly, at Windsor Castle.

The couple, both 30, exchanged vows in St George's Cathedral in front of 300 guests including the Queen, the Duke of Edinburgh, the Prince of Wales and the Duchess of Cornwall.

Cheers and clapping were audible outside the chapel as the newlyweds walked down the aisle. They posed briefly for pictures before heading off for their reception.

The bride wore a dress by Sassi Holford and a tiara borrowed from her new mother-in-law, the Princess Royal.

Prince Harry also attended with his girlfriend Chelsy Davy, who he introduced to his grandmother for the first time.

Among the six bridesmaids was the groom's sister Zara, whose boyfriend, England rugby player Mike Tindall, also attended.

Harry's brother, Prince William, was notable by his absence. He was in Kenya where his close friend Jecca Craig's brother Batian was marrying British-born Melissa Duveen.

Representing William at Windsor was his girlfriend Kate Middleton. Her presence was said to be a clear signal that she has been fully accepted into the Royal Family.

Sadly for the bride, showers dampened her arrival at St George's Chapel, but the rain had begun to subside for her beaming exit from the service as Mrs Autumn Phillips.

The couple were whisked away in a horse-drawn Balmoral Sociable carriage for a reception and dance at Frogmore House, Windsor, which has been lent to them by the Queen and Duke of Edinburgh.

The bride was a former Roman Catholic and has only recently been accepted into the Church of England. If she had not changed churches, Peter would have had to give up his right to become king.

Peter, the 11th in line to the throne, met his now-wife in 2003 at the Montreal Grand Prix where they were both working.

Initially he did not tell Miss Kelly that he was the Queen's grandson and she only found out when she spotted him in a programme about Prince William.

He proposed to her last July during a rain shower as they walked their dog.

He had intended to pop the question during a hot-air balloon ride but bad weather meant that his extravagant plans had to be abandoned.

The new Mrs Phillips was described by Fergus Gladstone, a school friend of Peter and one of his ushers, as "a genuinely cool girl".

At the service Patrick Kelly, the bride's half-brother, did a reading from Chapter 3 of St Paul's letter to the Colossians and Princess Eugenie read Shakespeare's Sonnet 116.

© Independent Television News Limited 2008. All rights reserved.