Amy Winehouse's husband offered a fellow prisoner £20,000 to beat up Pete Doherty whom he accused of having an affair with his wife, the Old Bailey heard today.

Blake Fielder-Civil, 26, awaiting sentence for attacking a barman and then offering a bribe to cover it up, also feared his wife would be kidnapped, the jury was told.

While in prison before trial he was said to have told Richard Lyttle that he had received threats that the 24-year-old millionaire singer would be abducted. The evidence emerged today during a trial of two men accused of taking part in a contract killing.

Close: Pete Doherty kisses Amy Winehouse after his release from prison last month

Douglas Johnson and David Austin are said to have been offered £5,000 to kill wheelclamping boss Charlie Butler, who was shot in the neck outside his home in Dagenham in October 2004.

Mr Lyttle told the court that Austin had confessed to him while they were in Belmarsh prison awaiting separate trials.

However, it was while he was in Pentonville that Mr Lyttle met Fielder-Civil, who he said had found out about his wife's alleged affair "when he learned he had been around there in the early hours of the morning".

Questioned by defence barrister Sir Desmond de Silva QC, Mr Lyttle said Fielder-Civil had offered him £20,000 "to cause damage" to the 29-year-old Babyshambles front man.

"He said he would give £20,000 to anyone who done him - cause him injury - he was quite annoyed at the time."

Sir Desmond asked: "Because he believed there was an affair between Amy a nd Pe t e Doherty?"

Mr Lyttle replied: "Yeah." Sir Desmond: "Did he say 'smash him to pieces?' " Mr Lyttle: "That's what he said."

Sir Desmond: "There are a lot of hard men in prison?" Mr Lyttle: "I would say so, yes."Sir Desmond: "

Kidnap fear: Fielder-Civil thought Amy was at risk

But Mr Fielder-Civil seemed to have entrusted you with this business of carrying out this particular mission?" Mr Lyttle: "He seemed quite upset and annoyed."

He went on to say that he had felt sorry for Fielder-Civil who had treated him as a friend, but admitted that he later tried to obtain £5,000 from a newspaper about what he had been told.

The witness also said that Winehouse's husband had told him "he had got a threat off a couple of geezers that said they were going to kidnap Amy".

"When you got that information about the possibility of the kidnap was it true?" asked Sir Desmond. "It was told to me by Mr Fielder-Civil. He said that people had been threatening him by having his wife kidnapped - that's what he said they might do."

Sir Desmond also questioned Mr Lyttle about his threat to burn down a taxi company if they did not pay him £3,000 in November 2004.

He admitted he had been convicted of blackmail over the threat but said he had been so drunk he could not remember making it and had no intention of carrying it out. Austin, 41 of New Addington, and Johnson, 27, of Thornton Heath, deny murder.

The case continues.