Actor Jake Gyllenhaal claims he's already forgotten filming gay sex scenes with his Brokeback Mountain co-star Heath Ledger.

The controversial film sees the actors playing lovers in the 1960s, and while it won't be released in the US until 9 December (05), Gyllenhaal insists his love scenes with Ledger are already far removed his memory.

He says, "I don't really remember much of that day... At a certain point, you just take a deep breath and dive in. And then the water's freezing, and you jump out as fast as you can."