"Casey Affleck and Summer Phoenix have amicably separated. They remain very close friends," Affleck's rep told the magazines in a statement on Wednesday.
It's unclear if and when the couple will file for divorce. His rep did not immediately respond to The Times' request for comment.
Affleck, 40, and Phoenix, 37, who've been an item for 16 years, wed in June 2006 and have two children together: sons Indiana, 11, and Atticus, 8. They costarred in the 2000 comedy "Committed" and the 2002 play "This Is Our Youth" with Matt Damon.
Affleck earned an Academy Award supporting actor nomination for playing Robert Ford in 2008's "The Assassination of Jesse James by the Coward Robert Ford" and is currently generating Oscars buzz for next year with one of his many projects, the drama "Manchester by the Sea," which premiered at the Sundance Film Festical in January. The "Oceans Eleven" alum also appears in the crime drama "Triple 9," which opened in late February, and has a starring role as explorer Meriwether Lewis in HBO's sprawling miniseries "Lewis and Clark."
Affleck appears to be following in the footsteps of his older brother in a whole other way: Ben Affleck and his wife,
That higher-profile union has been back in the news thanks to promotional appearances pegged to both parties' upcoming films, his "Batman v Superman" and her "Miracles From Heaven." Garner's bombshell Vanity Fair interview last month, which addressed the unraveling of their marriage, garnered a response from Affleck in a New York Times profile published this week.
"She felt like she wanted to discuss it and get it out there and get it over with so she could say, 'Look, I already talked about it — I don't want to do it again,'" he told the newspaper.
"It's fine," he said. "She's allowed to talk about it."
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