McManus won the most recent of his 26 caps in a 3-2 defeat by Spain at Hampden in October 2010, but he is keen to make sure it is not his last.
The 30-year-old, who made 21 appearances last season for Middlesbrough and loan club Bristol City, is aiming to impress former Celtic and Riverside boss Gordon Strachan after signing a one-year deal at Fir Park.
“I have always said I’ll never retire from international football,” the centre-back told MFCTV.
“The only reason I will not be in squads is if the manager doesn’t pick me, it will not be from my own doing.
“I’m lucky enough I have got a decent relationship with Gordon Strachan but first and foremost you need to play well with your club.
“Obviously I still have aspirations to play for my country but you need to be playing well week in, week out and that’s what I’ll be trying to do.”
McManus spent last week training with Hibernian after a similar stint with Motherwell but the Lanarkshire-born defender had already been won over by the spirit at Fir Park.
“From the minute I came in the door for the first time, there was a real family atmosphere about the place and that is what drew me to the club,” the former Celtic captain said.
“I had a couple of days at Hibs, which was great, they were really good as well and there are some lovely people over there.
“But when I came in here I had a fair idea I was going to come here, even though it has probably been the hardest decision I’ve had to make.
“But I feel as if I have made the right one and I’m looking forward to playing some games.”
McManus had attracted interest from clubs in England but was keen to be near his family, a situation similar to that of his Scotland team-mate James McFadden.
McFadden is expected to sign a contract, possibly today, and the pair could feature in the Fir Park friendly against Newcastle tonight.
“I have spoken to James quite a bit during the summer,” McManus said.
“Everyone knows how good a player he is and it would be nice to see him here.
“I know all the fans would love him to be here and I would certainly look forward to playing with him again.”