The pair became tabloid sensations in the U.K. after falling in love on reality show I'm A Celebrity... Get Me Out of Here in 2004. They wed in 2005 but went through a bitter divorce after almost four years, and finalised their split last September (09).
A month later (0ct09) Price claimed Andre was dating his manager/agent Claire Powell on a U.K. chat show, which led Powell to sue for substantial damages.
The Aussie singer also filed a writ accusing his former wife of slander and libel, requesting a judge to issue an injunction to prevent Price from issuing "similar words defamatory of the claimant".
He is seeking damages and the pair is expected to testify at London's High Court when the case is heard next week - revealing the real reason their marriage broke down, according to News of the World.
A source tells the publication, 'Katie thinks the case is a waste of time. But Peter's sick and tired of having to worry over what she's going to say about him next. There'll be a lot of revelations about the end of their marriage."
The impending court case comes at a bad time for Price - she was recently fined $1,500 (£1,000) after she was found guilty of failing to maintain full control of a luxury horsebox and was pelted with eggs during a meal with her family in Sussex, England on Friday (01Oct10). A police investigation has been launched.