JOHNNY Depp has reportedly accused Amber Heard of starting an affair with Tesla tycoon Elon Musk just one month into their 2015 marriage.

The shocking allegations are said to form part of a $50m defamation lawsuit Depp filed against his ex-wife after she accused him of domestic violence.

6 Johnny Depp and Amber Heard married in 2015 after meeting on the set of their movie 'The Rum Diary' Credit: Reuters

The Hollywood movie star has labelled his ex-wife's abuse claims 'an elaborate hoax' to 'generate positive publicity' for her career.

In the lawsuit obtained by People, the actor also alleged his 32-year-old wife would receive 'late night' visits from Musk while he was out of the country filming.

He also claims the outspoken billionaire was allowed into the couple's Los Angeles home the night Heard showed 'her battered face to the public'.

Heard and Depp separated in May 2016 - nearly eight months after they separated.

According to the US report, a representative for Musk claimed: 'Elon and Amber didn’t start seeing each other until May 2016.

'Their relationship didn’t become romantic until some time later.'

Depp is suing his ex-wife citing an article she wrote for The Washington Post about domestic abuse.