AMANDA Abbington has opened up about her "upsetting" split from long-term partner Martin Freeman and admits it was tough filming scenes for the new Sherlock episode together.

The couple, who had been together for 16 years, shocked fans when they announced their break-up before Christmas.

4 Amanda Abbington has opened up about her split from Martin Freeman Credit: Getty Images

4 Martin Freeman and Amanda Abbington will return as Doctor and Mrs Watson in tonight's episode of Sherlock Credit: BBC

Ahead of the new episode of Sherlock, which will air on BBC One tonight, Amanda said it was tough filming scenes of their characters, Mary and John Watson, being new parents.

Speaking to the Sunday Telegraph's Stella magazine, she said: "Yes, [it was] so weird. Especially playing new parents again, up all night feeding and things, because we were effectively revisiting how it was when we first got together."

Despite admitting there were "pressure points" during filming, Amanda said she would love to work with her ex again in the future.

The 42-year-old also insisted the split was amicable and the pair remain on good terms for the sake of their two children.

"Martin and I remain best friends and love each other, and it was entirely amicable, but we realised we'd come to the end of our time together.

4 Amanda admitted there were 'pressure points' while filming with her ex Martin Freeman Credit: Rex Features

"It is sad and upsetting, because you think you're going to be with someone forever, but you either do that or you break up.

"And we both came to the decision that splitting was best for us. We've been really lucky to make it such a clean break, especially for the kids."

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Martin, who is known for roles in The Hobbit and The Office, also opened about filming with his ex earlier this year.

He told the Guardian: "So we did this series not being together, which was kind of odd, although we were doing it as friends and we’re still very close.

"It’s always interesting doing stuff with your partner because you know each other better than anybody else and that was obviously still the case with this series."

Meanwhile, The Sun exclusively revealed that Amanda was spotted getting close to actor Jonjo O'Neill, best known for his role in The Fall, at a North London pub.

They were enjoying a drink at The Spread Eagle in Camden with another pal and seemed pretty taken by each other.

A source said: “They were with another male friend for a couple of hours and left about 8pm. She had her hand on her man’s thigh and they seemed pretty close.

4 The actress was spotted getting close to actor Jonjo O'Neill at a Camden pub Credit: Rex Features

“Punters recognised her but she didn’t seem to care who saw. It was quite clear she’d split from Martin. They were very close.”

The pair have also exchanged flirty messages on social media but have yet to confirm a romance.

Sherlock returns to BBC One on New Year's Eve at 8.30pm.

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