I know the truth Reason Kate Moss testified in Johnny Depp and Amber Heard’s trial

British model Kate Moss has explained why she decided to testify in ex-boyfriend Johnny Depp’s defamation trial against Amber Heard.

Kate Moss has opened up about why she chose to testify on behalf of ex-boyfriend Johnny Depp during his highly publicised defamation trial against Amber Heard.

Speaking with BBC radio show Desert Island Discs, the British model explained her decision to support the Pirates of the Caribbean star.

“I believe in the truth and I believe in fairness and justice,” the 48-year-old said.

“I know the truth about Johnny.

“I know he never kicked me down the stairs. I had to say that truth.”

Moss was in a relationship with Depp from 1994 to 1998. Picture: Patrick Hertzog / AFP.

Moss was in a relationship with Depp from 1994 to 1998. Picture: Patrick Hertzog / AFP.

In May, Moss, who dated Depp from 1994 to 1998, testified the Edward Scissorhands actor never pushed her down a flight of stairs during a vacation in Jamaica – contrary to a rumour spread by Amber Heard.

“We were leaving the room and Johnny left the room before I did,” she told the court.

“There had been a rainstorm. And as I left the room I slid down the stairs and I hurt my back.

“I screamed because I was in pain and I didn’t know what had happened to me.

“He came running back to help me and carried me to my room and got me medical attention.”

In her four-minute testimony, the glamour girl was asked by Depp’s lawyer if he ever pushed her down the stairs during their four year relationship.

“No. He never pushed me, kicked me or threw me down any stairs,” she said.

Depp sued ex-wife Amber Heard for defamation after she wrote an op-ed in The Washington Post referring to herself as a ‘public figure representing domestic abuse’. Picture: Michael Reynolds / Pool / AFP.

Depp sued ex-wife Amber Heard for defamation after she wrote an op-ed in The Washington Post referring to herself as a ‘public figure representing domestic abuse’. Picture: Michael Reynolds / Pool / AFP.

Amber Heard was ordered to pay Johnny Depp AU$14 million for defamation. Picture: Shawn Thew / Pool / AFP.

Amber Heard was ordered to pay Johnny Depp AU$14 million for defamation. Picture: Shawn Thew / Pool / AFP.

The Dark Shadows star sued his ex-wife for $70 million, claiming she defamed him in a 2018 Washington Post opinion piece in which she described herself as a victim of domestic abuse.

Depp was not named in the essay, but he said it clearly referenced him – and ruined his career, damaged his reputation and lost him tens of millions of dollars.

The Aquaman actress was ordered to pay Depp $US15 million ($A21 million) in defamation compensatory damages and $US5 million ($A7 million) in punitive damages.

However, Virginia law only allows punitive damages up to a maximum of $US350,000 ($A490,000), meaning Depp was awarded a total of $US10.35 million ($A14.4 million).

Heard has filed to appeal the jury verdict.