"The Crown" actress and "The History Boys" star released a joint statement to Metro which read, "We have separated and have been for some time. We do however continue as great friends with the utmost respect for one another."
The former couple wed in 2014 after meeting on the set of "Season of the Witch" in 2011. They welcomed their first daughter Ivy Rose in February 2015.
A friend of the 33-year-old SAG-winning actress and "The Bank Job" star revealed to The Sun, "After seven years together this came as a real shock to many of their friends, but they're lovely people and are determined to keep everything civilised."
"Obviously it has been a very sad period for both of them, and for their wider families. But they are wonderful parents, intelligent and both successful in their own right," the pal continued. "They've just decided that unfortunately their relationship simply wasn't working and that this would be for the best."
The separation arrives only weeks after Stephen revealed that he had a benign brain tumor, which doctors found on his pituitary gland at the end of 2016, removed in the summer of 2017. "You realize you're not the most important person in that process, and everybody who loves you goes through far worse. My daughter didn't know what was going on at all. But my family did, and I could see it in them," the 38-year-old actor told The Sun.
Claire herself had her own health troubles as she had a tumor in her eye which was benign when she was 17 years old. "It was horrible and debilitating, but it made me realize that I needed to grab the life I wanted," the Queen Elizabeth depicter opened up.