Charvis, who has been named Newcastle captain in succession to last season's co-skippers Jonny Wilkinson and Ian Peel, missed Wales' Grand Slam-winning RBS 6 Nations campaign because of injury.
But the 32-year-old has no intention of stepping down from representative rugby, and wants to fight for recognition in coach Mike Ruddock's Grand Slam squad.
"I spoke to Rob Andrew (Newcastle rugby director) and to Mike Ruddock about it, and I still feel there is unfinished business as far as my international rugby is concerned," said Charvis.
"I could take the easy way out and call it a day now, but I want to play again for Wales.
"They have a lot of competition for places in the back row with some great young players coming through, and it may well be that I am not selected, but I'm not throwing the towel in yet.
"I want to give myself every chance of being picked, and the one thing that's certain if I retire from Test rugby at this stage is that I won't even have a chance.
"Who knows what will happen in the future? I can only speak as I find myself today, but I still have the drive within me to be a success for both Wales and Newcastle."
Andrew has no doubt about 77 times-capped Charvis' leadership qualities in the Premiership, adding: "Colin has been nothing short of sensational since he joined us last year.
"People who don't know him well said at the time that he was trouble, that he was bad with the press and all that sort of stuff, but I can honestly say we haven't had a single problem with him.
"The fans love him, the players and coaches get on tremendously with him, and he has been spot-on with the press up here.
"He loves it in Newcastle because the Geordies just let him have the privacy he needs to get on and live his own life.
"He is a man who says what he thinks if he sees something wrong, and while some people in the Welsh press or on the terraces may have had problems with that, I only see it as a positive thing."
Andrew, meanwhile, also believes it is important for England and Lions fly-half Wilkinson to "focus on his own game".
Wilkinson's well-chronicled injury problems surfaced again on the Lions' New Zealand tour, ruling him out of third Test contention, and he clearly needs a long uninterrupted run of competitive rugby to try and help recapture former glories.
"Jonny just needs to focus on his own game and get back on the horse," added Andrew.
"He might not agree with me, because he doesn't like not doing things, but he will still have his piece and will be a big part of our future success here, as will Ian Peel, who was joint captain last season alongside him."