Liza Minnelli is in the midst of several legal cases

The 58-year-old said David Gest and bodyguard M'Hammed Soumayah were in regular contact with one another.

She added that Mr Gest claimed he had witnessed the attack on Mr Soumayah, contrary to earlier court papers.

Mr Soumayah has accused Ms Minnelli of forcing him into sex, while Mr Gest said she repeatedly assaulted him.

Ms Minnelli's complaint to the Manhattan Supreme Court said the pair "allied themselves in order to litigate these matters in the press, for the express purpose of bolstering each other's claims."

Mr Gest issued a press release shortly after Mr Soumayah commenced legal proceedings, saying he had witnessed the assaults and was prepared to testify against his estranged wife.

The singer and husband David Gest are locked in a legal battle

Ms Minnelli added in her complaint that the bodyguard, 56, said he had never seen her behaving violently.

Mr Soumayah is currently suing his former employer for $100m (�54m), claiming that she had made "many repeated attempts" to coerce him into sex, with his eventual capitulation.

Ms Minnelli countersued him for $250,000 ($124,000) for breach of contract, and dismissed the claims as "a quicksand of untruths and misstatements".

She said he broke a confidentiality agreement by passing on personal information about her to Mr Gest.

Divorce

Mr Gest, 52, issued his own legal action against Ms Minnelli for $10m (�5.3m), in October last year, claiming that he was repeatedly beaten during their 15-month marriage and suffered nerve damage in his head as a result.

The pair are suing each other for divorce, while Minnelli has filed a separate claim that Gest allegedly stole $2m (�1.55m) from her.

The couple were married at a glittering, star-studded ceremony in March 2002, with Elizabeth Taylor as maid of honour and Michael Jackson acting as best man.

Ms Minnelli and Mr Gest separated in July 2003.