After months of speculation, The Expendables 3 star/writer Sylvester Stallone confirms that Mel Gibson has signed on to play the villain, with Antonio Banderas also joining the cast for an unspecified role.

We first reported in June that Mel Gibson was playing the primary antagonist in this action sequel, after Sylvester Stallone revealed that he wanted him to direct back in April. Then, in July a report surfaced that Mel Gibson had not officially signed on yet, but now he is on board.

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While it isn't known who Antonio Banderas is playing, the actor will reunite with Sylvester Stallone for the first time since they starred in the 1995 action-thriller Assassins.

The actors join Jason Statham, Arnold Schwarzenegger, Kellan Lutz, Ronda Rousey and Harrison Ford, with Jackie Chan, Wesley Snipes and Milla Jovovich in talks to star as well. Both Mel Gibson and Antonio Banderas will next be seen in director Robert Rodriguez's Machete Kills next month.

Patrick Hughes is directing from a screenplay by Sylvester Stallone and Richard Wenk. It isn't known when production will begin, but it should be sometime this fall.