The duo reprised their FBI agent characters Dana Scully and Fox Mulder after a 14-year break for the 2016 miniseries, and the six-episode season ended in February (16) on a cliffhanger, which creator Chris Carter said "leads you to believe there’s more story to tell."

He said "with a certain amount of certainty" there will be more X-Files stories in the future, but Gillian claims neither she nor David have been approached by the network about more episodes.

"They haven't come to us. I don't know, it is again all about schedule," she tells U.K. host Jonathan Ross. "It's about whether it matches up. If it matched up and a few other things were in place - You know, we're not getting any younger... All the boxes need to be ticked. You know what I mean."

Gillian, who also stars in British TV drama The Fall, pushed for the recent revival to be a third film rather than a full series due to scheduling, but all parties finally comprised on a miniseries.

She adds, "They had never talked about it being a series, which we would have said no to. We were trying to get it done as a third film, which they also kept saying no to. It was kind of timing and it was also the fact that we could only do six rather than 22."

Gillian and David were co-stars in the original run for nine years and more than 200 episodes and the close proximity meant they drove each other crazy.

She joked they had tension "for a long time" on set but they are now closer then ever, adding, "We've always gotten along and we've been decent friends but we were down each other's throats for so long... We were always together... We were too much together but we're incredibly friendly now."