Wedding day dash for Zara's horse-riding best friends

The inaugural trials, on the outskirts of Edinburgh, are taking place this weekend, with dressage on Saturday and cross-country and show jumping on Sunday. Yesterday, organisers of the event announced that they have arranged for competitors with royal wedding invitations to ride in the morning, allowing them time for a swift change of clothes before heading to Canongate Kirk in Edinburgh for the afternoon marriage ceremony.

Miss Phillips, the Queen's eldest granddaughter and 13th in line to the throne, is herself an eventing world champion, and several of her invited guests are due to ride at the Hopetoun event.

William Fox-Pitt, the world No 2 in eventing, and Irish showjumpers Elizabeth Power and Jayne Doherty, got to know the bride through competing together and all received invites to the big day.

"I was always intending to come to Hopetoun, but it is great to be able to come to these two events on the same weekend," Ms Power, 26, said. "I will do the dressage early on Saturday before heading to the hotel in Edinburgh to get ready for the wedding."

Event director Stuart Buntine said: "We have deliberately given wedding guests early dressage times so they can do their test before the celebrations and then come back on Sunday to complete the show jumping and cross country phases."

Few details have been released about Saturday's wedding.

The ceremony will take place at Canongate Kirk in the Royal Mile, and is expected to be at 3pm, although that has not been confirmed, with the reception at the Palace of Holyroodhouse.

Guests are expected to include the Queen, Prince Charles and the Duchess of Cornwall and the Duke and Duchess of Cambridge.

The Hopetoun trials would have hoped to attract Miss Phillips herself to their event, had it not clashed with her wedding day - while other horse-riding guests also decided not to take part.

The riders who are doing face a cross-country ride and showjumping the morning after, so may have to go easy on the champagne at the reception.

A spokeswoman for the trials said: "They know Zara Phillips through eventing. They're all friends - Elizabeth said she met her on the Olympic circuit.

"Like any sport they spend a lot of time travelling around together, and that's how they get to know each other."It would have been so much fun if she (Miss Phillips] had been able to compete, but perhaps that would have been a step too far.

"Several other riders would have come, but are going to the wedding and just want to enjoy that and not worry about the horses."

Tom Murray, head of private clients and charity at Gillespie Macandrew, which is sponsoring the trials, said he hoped the two events would complement each other. "It's great that people can enjoy two major public events in Edinburgh on the last weekend in July"

The couple were introduced by Prince Harry in a bar in Sydney in 2003, when Mr Tindall was part of the World Cup-winning England rugby team.

Among the rugby players expected to be at the wedding are Mr Tindall's fellow England internationals Iain Balshaw, who is best man, and groomsman James Simpson-Daniel.