The girlfriend of murdered Brighton backpacker Peter Falconio sensationally admitted having a secret lover in Australia.

Joanne Lees, a travel agent from Hove, was sleeping with the other man behind Peter's back in Sydney.

Asked if it had been a sexual relationship, she replied: "I'm going to answer yes - but I wouldn't class it as an affair or a relationship."

She confirmed she had suggested a later rendezvous with the man, known only as Nick, in Berlin after completing her tour of Australia with Mr Falconio, 28.

The admissions came as Miss Lees, 30, was cross-examined during a court hearing in Darwin to determine whether there is enough evidence to prosecute Bradley John Murdoch for the murder of Mr Falconio in July 2001.

Grant Algie, representing Murdoch, said the admissions cast doubt on the credibility of the evidence given by Miss Lees, who is chief prosecution witness.

He described how she kept a secret email account to correspond with Nick, using the pseudonym Steph, as she toured the country.

He said days after the ambush in the outback during which Mr Falconio was shot dead, she told police she needed to delete some emails.

Miss Lees also revealed she had been paid £50,000 for an exclusive interview with a British TV channel.

Prosecutor Rex Wild objected to the questioning but Mr Algie argued it was relevant.

Miss Lees said she no longer had an exclusive relationship with Granada Television.

Miss Lees finished her testimony late this morning and was expected to fly home today. The pre-trial hearing continues.