The 25-year-old did not make an appearance for the Gulls after joining them on a one-year contract in July.
His only match this season was Gibraltar's 4-0 friendly defeat by Euro 2016 champions Portugal.
"I doubt many Conference managers have had an international as their number two keeper," said boss Kevin Nicholson.
"I don't want to stand in his way, for someone who's got such a unique opportunity of international football."
Robba, who has eight caps, has had his Torquay contract cancelled by mutual consent and is set to return to Gibraltar to play in their domestic league.
A loan move had been explored for the keeper, but Fifa rules meant the Devon side would not have been able to recall him if regular goalie Brendan Moore picked up an injury or suspension.
"With him being behind one of the best goalkeepers in the league he hasn't had any chances and a by-product of that, and it's a strange one because not many Conference managers have this issue, is that it's been hurting his international chances," Gulls player-boss Nicholson told BBC Radio Devon.
"He's going to go over there and he's going to play - hopefully he's going to get himself back in the fold internationally, but I haven't closed the door on him."
Gibraltar goalkeeper Jamie Robba has left National League club Torquay United in search of more game-time to cement his place in the national side.