Roberts, who signed for City from Fulham in 2015, has been linked with a permanent switch to Parkhead.
And speaking to the Scottish Sun, he admitted his future remains unclear.
When quizzed on the prospect of joining Celtic full-time, the England Under-20 international said: “We'll see. I'm just focused on finishing the last few games of the season on a high, like I did last season, and get the trophies we're aiming for.
“Then I'll go on holiday and we'll see where it takes me from there, start the season fresh again and hopefully be injury-free."