Johnny Depp wrote messages in blood on a mirror after a broken bottle slashed his finger during a row with his ex-wife, a London court heard on Thursday.

The actor claimed his ex Amber Heard threw a glass bottle at him during an altercation at the pair's rented Australian home in 2015 and it shattered when it hit a bar on which his hand was resting, cutting open a finger and exposing the bone.

Rather than get it stitched up immediately, the 57 year old "used the blood from the severed tip of his finger to paint messages on a mirror". He did later seek hospital treatment after experiencing "considerable pain".

The drama was recalled amid Depp's ongoing libel trial against News Group Newspapers and The Sun editor Dan Wootton, who called the Pirates of the Caribbean star "a wife beater" in a 2018 article.

The actor has always maintained he was never violent towards his ex, despite her claims, and insists he was the victim of her fiery outbursts, of which the alleged bottle throwing incident was one.

Giving evidence at London’s Royal Courts of Justice, Depp said he could see "bone sticking out" after Heard allegedly threw the bottle, cutting off the tip of his finger. Heard denies injuring his finger.

The incident reportedly occurred during a very unhappy stage of Depp and Heard's short-lived marriage, while he was filming Pirates of the Caribbean: Dead Men Tell No Tales Down Under.