The former Olympic equestrian competitor is angered by allegations of widespread corruption in the selection of cities to host the games, according to The Sunday Telegraph.

The princess is due to speak out in favour of a return to traditional Olympic values of fairness and integrity when she attends an International Olympic Committee (IOC) meeting on drugs in sport on 3 February.

The IOC temporarily expelled six members on Sunday and asked them to resign. IOC head Juan Antonio Samaranch apologised for their behaviour and spelled out reforms.

Buckingham Palace told the Sunday Telegraph the Princess was monitoring events closely.

She is one of two British delegates on the IOC. The other, Craig Reedie, chairman of the British Olympic Association, said: "The Princess Royal wants to put its own house in order."

Princess Anne does not accept gifts while representing the IOC.

Athletes back reform

Tessa Sanderson: "Appalling"

Former British Olympic javelin thrower Tessa Sanderson, who won gold in Los Angeles in 1994, echoed demands for change within the IOC.

Tessa Sanderson: "Sack guilty parties"

She said officials found guilty of corruption should lose their jobs.

Two IOC officials resigned last week. Seven more face expulsion.

Another former Olympic athlete, Jon Ridgeon, said corruption had been going on for years, but now officials were being forced to clean up their act.