"Obviously there are the goals of winning the Top 14 and getting to the latter stages of the Heineken Cup," he told television station France 2. "Those are the team goals, but personally I want to improve my rugby and playing in a competition I am not used to is really going to challenge me. Hopefully I will become a better player with this experience."
He added: "I saw the game (against Leicester on Saturday) and got a bit of the taste of the style of rugby we play, and I'm looking forward to being a part of it next weekend.
"Playing in the Heineken Cup was a big part of my decision. My first match will be in that competition and I can't wait."
Carter was one of six players registered as "Additional Players" for Round 4.