Brad Pitt says being engaged to Angelina Jolie "makes sense."

The Killing Them Softly star proposed to his girlfriend - with whom he raises six children - earlier this year but insists they have not yet set a wedding date as they are hoping to stand by their previous pledge not to tie the knot until gay marriage is legal.

"We actually, really and truly, have no date. It's just something that makes sense to us, and certainly date-wise, it's just a rumor. We're still hoping that we can figure out marriage equality in the states before that date," he said.

Brad also revealed the couple are keen to work together again. When asked if they would consider making a film together again during a press conference at the Cannes Film Festival, he said, "Yeah, we'd love to."

Brad is said to have proposed to Angelina following encouragement from their eldest son Maddox, 10, arguing it would bring some normality to their family life.

"Maddox wanted them to have a wedding. He was the most vocal in pushing for it. Brad pleaded and said that everything else in the kids' lives is not normal. He added that they travel constantly, they are always in different houses and different schools. They needed to give the kids one thing in their life that is normal, and they are asking for this. He said they should do it for them," a source told US Weekly.