"Kate and Sam are saddened to announce that they separated earlier this year," confirmed lawyers for the Oscar-winning actress.
The statement added: "The split is entirely amicable and is by mutual agreement. Both parties are fully committed to the future joint parenting of their children."
Winslet married Mendes, whose box office hits include American Beauty, in a secret ceremony in May 2003 on the island on Anguilla in the Caribbean. They have a son together, Joe Alfie Winslet Mendes who was born in New York on 22 December 2003.
The pair began their relationship after Winslet split from director Jim Threapleton in 2001, with whom she had daughter, Mia Honey, 9.
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