Watts, 47, and Schreiber, 48, said that “the best way forward for us as a family is to separate as a couple.”
“It is with great love, respect and friendship in our hearts that we look forward to raising our children together and exploring this new phase of our relationship,” they said, asking for privacy for their two young sons.
Their separation follows on the heels of Hollywood power couple Brad Pitt and Angelina Jolie’s sudden divorce announcement last week.
Australian actress Watts, who has been nominated or two Oscars, and Schreiber, the star of “Ray Donovan” have been involved since 2005 and have never been married. Watts had previously dated Australian actor Heath Ledger.
Watts and Schreiber star together in the upcoming boxing drama “The Bleeder.” Schreiber will also star on Broadway in “Les Liaisons Dangereuses,” opening next month, in which he plays a promiscuous Frenchman.