Didn't get an invitation to Friday's big event? Well, don't feel too bad--you're in pretty good company.

In a snub that's raised some eyebrows in Britain, neither of the country's two most recent former prime ministers received an invite. Also left out are President Obama and first lady Michelle Obama.

There's no place for either Tony Blair or Gordon Brown among the 1,900-member congregation, even though the other two living former British leaders, Baroness Margaret Thatcher and Sir John Major, were invited. (Thatcher, 85, has declined, citing her health, but Major will be there.) Adding to the awkwardness, when Prince Charles and Lady Diana were married in 1981, all surviving prime ministers attended.

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"It's a surprising selection," one Labour member of Parliament has said. Another described it as "odd."

St. James's Palace has explained the discrepancy by saying that, unlike Blair and Brown, Thatcher and Major are Knights of the Garter, England's highest order of Knighthood. It also has noted that, unlike the Charles and Diana wedding, this one isn't an official state occasion, because William isn't the prince of Wales.

"There is no protocol reason to invite them, so unless [William and Kate] wanted to invite former prime ministers for a personal reason, there's no reason to do so," said a spokesman. "It is a private wedding, and the couple are entitled to invite whoever they want to it."

Fair enough. Still, the omission has some suggesting that politics played a role. Thatcher and Major are members of the Conservative Party, which traditionally has been supportive of the monarchy. Blair and Brown's Labour Party, meanwhile, has often had a less cozy relationship with the crown.

And some speculate that the strained history between the monarchy and Blair, who led Britain from 1997 until 2007, may also have factored in to the decision to leave him off. He famously clashed with the queen over her handling of Princess Diana's 1997 funeral, then in 2002 was accused of trying to take control of plans for the celebration marking the queen's 50th anniversary on the throne. And Blair's wife, Cherie, once refused to curtsy for members of the royal family.

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If Blair and Brown are suffering from hurt feelings, they can commiserate with Obama. In another break from tradition, he and Michelle are also on the outside looking in, even though President Reagan and Nancy Reagan were invited to the Charles and Diana nuptials. (Reagan was still recovering from an assassination attempt, so his wife went without him.) The Reagans also were said to have been invited to Prince Andrew's 1986 wedding to Sarah Ferguson, though it wasn't a state occasion.

William and Kate are understood originally to have wanted a smaller and more private wedding, modeled on the future queen's austere 1947 marriage to Prince Philip, which took place at a time when rationing was still in effect. But, in a development that everyone who has ever planned a wedding will understand, the event appears to have grown in scale and cost as the date has approached.

Indeed, though there's no room for Blair, Brown, or Obama, some less prominent dignitaries did make the cut. The king of Tonga and the crown prince of Abu Dhabi will both be in attendance, the palace has said, as will the governors-general of numerous former British territories, including Papua New Guinea, St. Christopher and Nevis, and St. Vincent and the Grenadines. Celebrities including David and Victoria Beckham, Elton John, and Guy Ritchie also will be in the congregation.

AP Photo/John Stillwell, Pool: The queen receives Tony Blair on May 6, 2005, at Buckingham Palace after his Labour Party won a third term in office.

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