Gillian Anderson was offered half the pay of her 'The X-Files' co-star in comeback series

Ms Anderson said it was “sad” that after first closing the pay gap in the 1990s, she had to fight the same battle in 2016

Gillian Anderson said she was first offered half the pay of co-star David Duchovny (Rex Features)

Award-winning actress Gillian Anderson was offered half the pay of her The X-Files co-star David Duchovny for the 2016 series, one decade after she managed to negotiate equal pay with the same studio.

Ms Anderson, who plays Fox network’s much beloved FBI special agent Dana Scully, managed to close the wage gap with Mr Duchovny, who plays agent Mulder, in the 1990s, but had to fight again for equal pay in 2016.

The news, first disclosed in the Hollywood Reporter, said that Ms Anderson was offered 50% the pay of her co-star.

“Especially in this climate of women talking about the reality of [unequal pay] in this business, I think it’s important that it [the pay gap] gets heard and voiced,” Ms Anderson said in an interview with The Daily Beast. “It was shocking to me, given all the work that I had done in the past to get us to be paid fairly. I worked really hard toward that and finally got somewhere with it.

The X-Files, which arguably heralded the success of serialized television, first hit screens in 1993, and Scully and Mulder's chemistry has lasted for nine seasons, two films and 25 years.

Ms Anderson received an Emmy and a Golden Globe by the fourth season as the agent and medical buff whose task is to disprove agent Mulder’s alien conspiracy theory.

According to The Daily Beast, Ms Anderson was required in the earlier series to stand a few feet behind her co-star on camera and never step side-by-side with him.

It took another three years before Ms Anderson managed to close the wage gap with Mr Duchovny.

“Even in interviews in the last few years, people have said to me, ‘I can’t believe that happened, how did you feel about it, that is insane.’ And my response always was, ‘That was then, this is now.’ And then it happened again! I don’t even know what to say about it,” Ms Anderson said.

Ms Anderson finally managed to negotiate equal pay for the series, the first episode of which was shown on Sunday night.