Celebrity couple Ashton Kutcher and Mila Kunis have apologised for the character letters they wrote on behalf of their That ’70s Show co-star Danny Masterson before he was sent to jail for rape.

On Thursday, a judge in Los Angeles sentenced Masterson to 30 years to life in prison for raping two women in his Hollywood Hills home in 2003.

Both Kutcher and Kunis jointly issued a joint statement through an Instagram video on Saturday, saying they were sorry for the pain the letters may have caused to the victims and their families.

“We support the victims. We have done this historically through our work and will continue to do so in the future,” Kunis said in the video.

Kutcher explained how Masterson’s family reached out to him and Mila to write character letters for their co-star whom they had known for 25 years. “The letters were intended for the judge to read and not to undermine the testimony of the victims or re-traumatise them in any way. We would never want to do that, and we are sorry if that has taken place,” he said.

Kunis said the letters were not written to question the legitimacy of the judicial system or the validity of the jury’s ruling. “Our heart goes out to every single person who’s ever been a victim of sexual assault, sexual abuse or rape,” she signed off.