This surprises me greatly. It shows a partisanship from the monarchy. How can the monarchy survive and diss one party?
Royal wedding: No place for Tony Blair and Gordon Brown
The former Labour prime ministers will not join the 1,900-strong congregation at Westminster Abbey despite it being a “semi-state” occasion that they had been widely expected to attend.
By contrast, both their Conservative predecessors, Sir John Major and Baroness Thatcher, received invitations. Lady Thatcher declined on health grounds although Sir John will be present when Prince William marries Kate Middleton.
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However, Labour MPs said it was “surprising” and “odd” that the pair had apparently been snubbed on what was a “great British occasion”.
All surviving former prime ministers, Harold Macmillan, Alec Douglas-Home, Harold Wilson, Edward Heath and James Callaghan, attended the Prince of Wales’s marriage to Lady Diana Spencer at St Paul’s Cathedral in 1981.
http://www.telegraph.co.uk/news/uknews/royal-wedding/8470465/Royal-wedding-No-place-for-Tony-Blair-and-Gordon-Brown.html