Spears and Federline married in September 2004

After Spears filed for divorce earlier this month, some tabloid papers claimed Federline would make the film public.

But his lawyers say it does not exist and "stories of Kevin attempting to sell such a video are patently false".

A US judge previously dismissed a libel action brought by the couple against a US magazine which claimed they had filmed a sexually explicit video.

The report, in Us Weekly, claimed that the couple watched the video with lawyers after a member of their entourage threatened to release the footage.

But the judge said that because the singer had "put her modern sexuality squarely, and profitably, before the public eye", the article was unlikely to be considered defamatory.

The issue of whether a tape actually existed was not explored at the legal hearing.

Worth $123m

Spears, 24, and Federline, 28, wed in 2004, just months after Spears annulled her marriage to childhood friend Jason Alexander.

They had their first child, Sean Preston, last year and announced the birth of their second son, Jayden James, in September.

In divorce papers filed earlier this month, Spears said she would seek custody of the two children, but Federline has started the legal process to challenge her claim.

Spears has sold more than 60 million albums since her pop debut in 1998 with the UK number one single, Baby... One More Time.

Her personal wealth was estimated at about $123m in 2004 by Forbes business magazine.

Federline, a former dancer who has recently released a rap album, has two children by his former partner, TV actress Shar Jackson.