The tight-head has been given a chance in the RBS 6 Nations through injury to Adam Jones but knows he will become an understudy at both club and country when the British Lions Test prop returns
.
"I'm leaving the Ospreys, but I'm not sure where yet because I have one or two options," Mitchell told the Western Mail.
"It's simply a playing issue. There's nothing wrong with the Ospreys and I have loved my time with them.
"But I want to play first-team rugby and I want to play for Wales. Some recent chances have come my way because of Adam's injuries, but if he wasn't injured, would I be playing?
"The door has been opened there for me, but I want to do it off my own back and be picked on merit. I don't want to be seen as someone who's keeping the jersey warm for Adam Jones.
"I'm a competitive guy. I want to compete for that jersey and playing is the way forward."
Mitchell produced another solid performance in Wales' victory at Murrayfield and is enjoying the chance to test himself at the highest level.
Many believed the Welsh scrum would become an Achilles heel during the Six Nations with Test Lions Jones and Gethin Jenkins both missing through injury. But Mitchell and co have held their own up front.
"I'm loving international rugby at the moment," added Mitchell.
"The big difference is the tempo; it's crazy. But I'm very ambitious and will do whatever it takes to play for Wales.
"The scrummaging started off really well, but then a couple of penalties went against us. They were iffy decisions, but we'll go by them and just take the result.
"We were under pressure, with results not having gone our way. But we're glad this one did go our way.
"I think the edge to the Welsh performance came from not winning for a while. We were aware of that and made a statement to ourselves that we had to win. Thankfully it came off.
"We started explosively and maintained that throughout the whole game. The boys were tired at the end, myself included, because we gave everything. It was a happy dressing room, with a lot of smiling faces, and rightly so because we got what we deserved."
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