Labour was at loggerheads with St James's Palace last night amid a growing row over a royal wedding day 'snub' to Tony Blair and Gordon Brown.
Whitehall sources revealed that ministers were not consulted by courtiers over a decision to exclude the two former Labour Prime Ministers from Friday's guest list.
Senior politicians on all sides are surprised at the move because both surviving former Conservative Prime Ministers, Baroness Thatcher and Sir John Major, as well as David Cameron, were invited to see Prince William and Kate Middleton tie the knot.
Choices: Kate Middleton's rogue uncle Gary Goldsmith is invited to the wedding but Tony Blair and Gordon Brown are not
If your name's not down... Former Prime Ministers Gordon Brown and Tony Blair have not been invited to the wedding
Among the more controversial guests is Kate's black sheep uncle Gary Goldsmith, who was initially ostracised by the family after being exposed as a cocaine user by a tabloid newspaper.
Also invited to Westminster Abbey are footballer David Beckham, pop star Sir Elton John and Madonna's ex-husband, film director Guy Ritchie.
But the absence of Mr Brown and Mr Blair last night caused Labour MPs to accuse the Royal Family of causing 'gratuitous' offence. They said Government officials should have warned of the potential for political controversy.
In 1981 all surviving Prime Ministers Harold Macmillan, Alec Douglas Home, Harold Wilson, Edward Heath and James Callaghan were invited to the wedding of Prince Charles and Lady Diana Spencer.
Royal sources told the Daily Mail that Prince William's wedding was not a full state occasion and there was therefore no reason to invite all former British leaders.
Officials said Lady Thatcher, who will not attend because of ill health, and Sir John were invited because they are Knights of the Garter the highest royal award for chivalry and their Labour successors have not yet been so honoured.
AND THE UNCLE WORE A TATTOO
Kate's errant uncle Gary Goldsmith topped up his tan at a sunbed centre near his central London mews home ahead of the wedding.
Mr Goldsmith, 45, displayed a new tattoo across his back the proverb 'Spend and God Will Send' which is an addition to the collection of stars and his initials on his upper right arm and a 'zipper' on his right leg.
The businessman was shunned by his furious sister, Kate's mother Carole, after being exposed as a cocaine user. He went into rehab and now he and his ex-wife have been invited to the wedding.
One source said it had 'simply not crossed Prince William's mind' to invite Mr Blair or Mr Brown, insisting: 'We have had to draw the line somewhere.'
But Labour justice spokesman Chris Bryant said: 'Those who have been Prime Minister have served this country, and I think that the same proprieties that have been followed on previous occasions should have been followed again.
'I blame Downing Street for not spotting it and saying, "We don't like Gordon Brown either, but he really should be there".'
Labour MP Graham Allen, chairman of the Commons political and constitutional reform committee, said: 'I don't think this is a constitutional issue, but I do think it's insensitive.
'It seems to raise a lot of questions. It makes you want to ask what the motive is. It seems to be picking a fight quite unnecessarily.'
Former Labour Europe minister Denis Macshane said he was tabling Parliamentary questions to establish exactly what involvement Government officials had in approving Friday's guest list.
'It is quite gratuitous to invite two living former Prime Ministers who are Conservatives, but snub the ones that are Labour,' he said.
'I would like to know what consultation there was with the Government. It's essential senior royals are never, ever associated with any party political bias. This is all rather a shame and leaves a worrying taste in the mouth.'
Senior Tory MP Eleanor Laing, the party's former justice spokesman, insisted the exclusion of Mr Blair and Mr Brown seemed 'perfectly reasonable'.
'There is something special about being a Knight of the Garter as far as the Royal Family is concerned, so I am not surprised by this,' she said.
Professor Rebecca Probert, of Warwick Law School, said: 'The wedding of Charles and Diana was very unusual in being held at St Paul's rather than Westminster Abbey the only royal wedding to be held there and St Paul's had a far larger capacity.
'Add to that the fact that the Prince of Wales was, and still is, the direct heir to the throne, whereas William is one step removed, and a difference in approach seems perfectly justified.'
A St James's Palace spokesman said: 'Sir John Major and Baroness Thatcher were invited as they are both Knights of the Garter, along with Prince William.
'Furthermore, Sir John Major has a personal connection to Prince William, as he was appointed guardian to Prince William and Prince Harry following the death of the late Diana, Princess of Wales.
'This is a private wedding and not a state occasion, unlike [the Queen's wedding] in 1947 or 1981, so there is no protocol reason to invite former Prime Ministers.
'The couple were in charge of their own guest list and worked closely with the Queen's and Prince of Wales's Households where necessary.'
A Downing Street spokesman said: 'The invitations for the royal wedding are a matter for the Palace, not the Government.'
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