Oscar-nommed JOSH BROLIN has been photographed in what looks like a steamy lip lock with a sexy actress – who isn’t his wife DIANE LANE!

The Jonah Hex star Brolin, 42, kissed and hugged 36-year-old married beauty Marley Shelton after a coffee date in Santa Monica, Calif., on April 28.

"Josh and Marley sat at an outside table at a cafe sipping coffee for at least 30 minutes and talking animatedly together. Josh was not wearing his wedding ring," said the witness.

"As they walked away, Marley reached out to put her arm around Josh’s shoulder.

"A moment later, they kissed full on the lips, Josh hugged Marley and she pulled him close with her free hand."

But Brolin’s rep insists nothing improper happened.

"Josh and Marley are dear, dear friends. They’ve done three movies together, and this was just an embrace between old friends," she told The ENQUIRER.

Yet Brolin’s marriage to Diane, 45, has been stormy in the past.

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