Their on screen chemistry is helping make ITV’s ‘Victoria’ unmissable TV every Sunday night, but it appears Jenna Coleman and her co-star Tom Hughes are having a romance off screen as well. The two actors have reportedly been dating since last summer, before they even started filming the period drama.

Jenna ColemanIs Jenna Coleman secretly dating Tom Hughes?

The Mail on Sunday reports that the two became an item after Coleman was linked to Price Harry. Hughes was said to be jealous that the royal was moving in on the actress and decided to pursue her himself.

“Ironically Harry is largely responsible for them getting together,” a friend told the newspaper. “Jenna caught Harry’s eye at the polo. They flirted and spent the evening together and Harry took her number and they saw each other a couple of times”

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“Tom was also on the scene and made it very clear that he wasn’t happy about Harry making a move on Jenna. They got together shortly afterwards.” However the couple aren't ready to go public with their romance yet.

"They have deliberately kept their romance below the radar because they are ‘deeply private’ people,” the friend added. “They’ve been together for months, on and off since last summer. Tom dumped his long-term girlfriend to be with Jenna and she chose to be with him even though Prince Harry was very keen on her. What started as an affair became a very serious romance.”

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On screen the sexual tension between Victoria and Albert is building and the pair's chemistry is said to be down to their real life romance. “The reason the chemistry is so tangible is because they are dating in real life. Those scenes are very real. They are completely hooked on one another,” a source close to Coleman said.

Coleman, who first met Hughes three years ago while filming BBC2 drama ‘Dancing On The Edge’ previously said of her co-star: “It is wonderful because we are very old friends and immediately we have the same tone, the same ideas, and instantly that connection feels very strong.”