Vettori, one of the world's leading all rounders, has been plagued by Achilles and back injuries and last played Test cricket 18 months ago. (Agencies)
The 35-year-old has now ruled himself out of a comeback at the World Twenty20 tournament in Bangladesh in March but said he is targeting New Zealand's tour of the West Indies in May as the series that will determine if he can revive his career.
"I want to commit to that tour otherwise it will be too hard to keep trying to come back," the left-arm spinner said following a meeting with McCullum and New Zealand coach Mike Hesson.
"Mike and Brendon made it clear that if I play for New Zealand again I've got to deliver in all three facets of the game, which is completely fair. I can't just bowl 24 balls and then expect to be hidden in the outfield."
Vettori is one of only three players -- behind Ian Botham and Kapil Dev -- to score more than 4,000 runs and take more than 300 wickets in Tests, and McCullum sees him as a vital member of the New Zealand team if fit.
"He's clearly a very well proven international cricketer and it will be nice if he was able to be part of the squad, but for him at the moment it's a matter of making sure he tries to get himself fit," McCullum said.
"Hopefully if that's the case we will see him in the West Indies. Obviously it's the selectors who make those calls but from my point of view he comes straight in."
Vettori last played a Test in July 2012 against the West Indies and his last internationals were three appearances in the 2013 Champions Trophy one-day series in England last June.
He recently played seven games in Australia's Big Bash league, with the help of painkillers, but said he was barely able to walk at the end.
"It was a little bit worse than the past. Running around was difficult. I'll just rest up and try and get that ready. If I can then that's great and if I can't then the writing is probably on the wall," he said.
Vettori, one of the world's leading all rounders, has been plagued by Achilles and back injuries and last played Test cricket 18 months ago.