The makers of Netflix show The Crown have apologised to its stars Claire Foy and Matt Smith after it emerged that she was paid less than him.
Production company Left Bank Pictures said the actors "have found themselves at the centre of a media storm this week through no fault of their own".
A statement said: "We want to apologise to both Claire Foy and to Matt Smith, brilliant actors and friends."
Foy played Queen Elizabeth II in the drama alongside Smith as Prince Philip.
The producers' statement added: "As the producers of The Crown, we at Left Bank Pictures are responsible for budgets and salaries; the actors are not aware of who gets what, and cannot be held personally responsible for the pay of their colleagues.
"We understand and appreciate the conversation which is rightly being played out across society and we are absolutely united with the fight for fair pay, free of gender bias, and for a rebalancing of the industry's treatment of women, both those in front of the camera and for those behind the scenes.
"We all have a responsibility to do what we can to ensure that these issues are tackled, and as a leading production company we want to make our contribution to the debate."
The company added that it was "engaged in conversations" with ERA 50:50, which lobbies for equal representation for actresses, and was "keen to talk" to the Time's Up movement.
The pay gap between Foy and Smith was revealed last week, when the producers said Smith was worth more because of his higher profile from his days in Doctor Who.
Foy was reportedly paid $40,000 (£28,000) per episode for the first two series of The Crown. It is unclear what Smith was paid.
According to Variety, co-producer Suzanne Mackie last week said that in the future, the lead actress would not be paid less.
"Going forward, no-one gets paid more than the queen," she said.
Olivia Colman will play the monarch in the third series. The identity of the actor playing the Duke of Edinburgh hasn't been revealed.