The attacking midfielder has a £8.4 million release clause.
The 24-year old has been linked with Tottenham in recent weeks and his comments suggest a move is a distinct possibility.
“I am here, as normal, I have a contract with Mainz and it is good to be back after the break,” said Malli.
“I cannot say (whether I will stay) right now, I just cannot rule anything out – what counts for me is the here and now.”
The Turkish international was approached by Borussia Dortmund in the winter transfer window and he admitted he would have liked the move: “I would have liked to go but the bid wasn’t accepted,” he said.
Spurs’ chances have been boosted by the fact that Malli wants to play Champions League football, he added: “We play in the Europa League next season, that is not so interesting.”
Juventus' Mario Lemina in action with Tottenham's Victor Wanyama
The Lilywhites have added Vincent Janssen and Victor Wanyama to their ranks so far this summer and look set to make Georges-Kevin Nkoudou their third signing imminently.
Tottenham's Heung Min Son scores
Heung-Min Son has failed to set the world alight following his move from Bayer Leverkusen last year and an injection of quality in the final third would be useful as Spurs prepare for a return to the Champions League.
Mauricio Pochettino’s men enjoyed an excellent campaign last year but struggled when they were forced to rotate and it is clear that more quality strength in depth is needed.