A jury at London's Snaresbrook Crown Court found him guilty of one count of supplying 2.036 grammes of cocaine to an investigative reporter, as well as a similar charge involving 11.9 grammes of cannabis resin.

Judge Stephen Robbins remanded Alford in custody until May 26 and told him that a prison term was 'inevitable'.

The verdict was greeted by gasps from the packed public gallery, and Alford's girlfriend, Tina Mahon, was seen to tremble and hold back tears.

In August 1997, Alford had been lured to the Savoy Hotel in central London by a journalist posing as an Arabian prince and secretly filmed supplying cocaine and cannabis.

The court heard Alford, 27, was so taken in by the "elaborate ... well-planned subterfuge" he even bowed to the bogus royal, who was in fact News of the World investigative editor Mazher Mahmood.

The prosecution said Alford had acted out of "greed" after being offered the chance to join a celebrity line-up at the fake sheikh's nightspot opening in Dubai.

Sacked after revelations

Alford, from Hadley Wood, Hertfordshire, represented himself during the 10-day trial.

He told the judge: "I respect the verdict of the jury and I thank your honour for your tolerance of my inexperience in these matters."

Before they delivered their verdict, Judge Robbins warned the five women and seven men trying the case they should not make decisions based on "emotion".

After the story broke last year, Alford was sacked from his £50,000-a-year role in the ITV television drama, based on the lives of a team of firemen.