The Irish striker has rejected an initial offer for a new deal with the Scottish champions but Lennon is hoping improved terms can get him over the line.
"He rejected our initial offer but I would imagine we'll come again and get him done," Lennon told the Sunday Mail.
"I'd like him to stay and I don't really think he wants to go, so we'll speak to his agent over the next week or so.
"It's not that it's taken longer than I thought. He has to think about his own future and is well within his rights to turn down the offer. I never doubted his commitment, just his discipline problems – the rascal in him."