Johnny Depp was seen smiling while Kate Moss delivered her testimony during his defamation lawsuit against Amber Heard.

The high-profile trial is expected to conclude this week and Depp's 48-year-old supermodel ex took to the stand to comment on her romance with the actor and an incident Heard referred to earlier in the trial.

Previously, the 36-year-old Aquaman actress described an altercation between her former husband and her sister Whitney Henriquez.

During the incident, Heard said: "I just see my little sister with her back to the staircase and Johnny swings at her and I don't even wait," she said, adding: "In my head, I just instantly think of Kate Moss and the stairs and I swung at him."

Watch Moss' testimony below:

[[youtubewidget||https://www.youtube.com/watch?v=AmfetXakOsc]]

Kate Moss testified via video link for three minutes on Wednesday (May 25) to clear up the rumor that Depp had allegedly pushed her down a flight of steps during their relationship which lasted from 1994 to 1998.

Depp’s attorney Benjamin Chew questioned Moss on whether anything had happened while they were on vacation at the GoldenEye resort in Jamaica.

"We were leaving the room, and Johnny left the room before I did, and there had been a rainstorm. As I left the room, I slid down the stairs and I hurt my back," Moss told the Fairfax courtroom.

"I screamed because I didn’t know what had happened to me and I was in pain. He came running back to help me, and carried me to my room, and got me medical attention."

The model was then asked whether the actor pushed her down the stairs during that day and she replied: "No."

Chew then asked her whether Depp had ever pushed her down the stairs throughout their four-year relationship and Moss answered: "No. He never pushed me, kicked me, or threw me down any stairs."

[[imagecaption|| Kate Moss and Johnny Depp in 1995. Credit: MediaPunch Inc / Alamy.]]

Depp could be seen smiling after her testimony, and earlier in the case his legal team seemed happy when The Rum Diary actress brought up Moss' name - giving them a reason to call her to the stand in the highly publicized trial.

Moss’s testimony came during the rebuttal phase of the long-running $50 million defamation trial.

The 58-year-old Pirates of the Caribbean star is suing Heard over a 2018 op-ed that she wrote for The Washington Post in which she claimed to be "a public figure representing domestic abuse".

The actor was not named in the article, but his legal team argues that it defames him and ruined his career and reputation. Depp has denied he ever physically assaulted Heard and says she was the abuser in the relationship.

Heard is countersuing for $100 million.

Featured image credit: REUTERS / Alamy.

Johnny Depp seen smiling as Kate Moss delivers her testimony