Relations between Mrs Parker Bowles and the Queen were strained

The Prince of Wales's partner has received a personal invitation to a Westminster Abbey service on 2 June, Buckingham Palace has confirmed.

This will be seen as a conciliatory move by the Queen and a step towards the acceptance of Mrs Parker Bowles within the Royal Family.

She may also be a guest at private family celebrations to mark the anniversary and at Prince William's 21st birthday next month.

Mrs Parker Bowles was at Princess Margaret's memorial service, at the invitation of the princess's daughter, Lady Sarah Chatto.

Religious fears

She also attended the Queen Mother's funeral and accompanied the Prince of Wales to last year's Golden Jubilee concerts in the grounds of Buckingham Palace.

But the invitation to the commemorative Westminster Abbey Coronation service is more significant.

The couple's marriage would pose constitutional problems

Some religious figures may have reservations about Mrs Parker Bowles attending, because the divorcee's relationship with the heir to the throne has threatened the stability of the monarchy.

The move could rekindle speculation on whether Charles and Camilla could marry.

Mrs Parker Bowles was blamed by Diana, Princess of Wales, for the breakdown of her marriage to Charles.

The Abbey service on 2 June is being broadcast live on BBC TV, radio and online.

It will be attended by senior members of the Royal Family, government ministers including Prime Minister Tony Blair and Commonwealth leaders from around the world.

More than 1,000 members of the public, chosen by ballot, will also be at the service.