The 31-year-old has not accepted the offer of a new contract to extend his seven-year stay in north London.
He said: “It’s no longer a secret, I will leave Arsenal for sure. The [contract] discussions have not gone as I wished.”
Former team-mate Lukasz Fabianski, 29, has joined Swansea on a free transfer. The goalkeeper also spent seven years at the Emirates Stadium and hopes to be installed as the Welsh club’s No1 stopper.
Despite having Michel Vorm for competition, he said: “I want to play week in, week out. It’s going to be a real fight but I’m not afraid of that.”