Attorney general Peter Goldsmith obtained a court injunction stopping the broadcast late on Friday following a request by police probing whether political parties awarded state honours in return for loans.

Police sought the injunction "because of their concern that disclosure of certain information at this stage would impede their inquiries", said a joint statement from the police and Goldsmith.

The move sparked speculation among politicians that officers were planning to bring charges against one or more people.

Two Blair aides were recently arrested on suspicion of perverting the course of justice as the probe appeared to widen into a potential cover-up inquiry.

Blair, who is set to step down this year after a decade in office, has been questioned twice as a witness by detectives investigating whether businessmen were offered honours for cash.

The injunction was granted shortly before the BBC was due to broadcast the story on its 10 o'clock news.