Ambrose, who signed for the Bhoys in the summer from Ashdod in Israel, has recently won the Africa Cup of Nations with the Super Eagles, their first major title in 19 years.
The defender is under contract until July 2015 and Lennon is optimistic Celtic will not have to sell him as soon as the next transfer window this summer.
“Efe has been brilliant for us and there’s been a lot of interest in him,” said Lennon according to The Scotsman. “There is definite interest from top teams, not just in England but on the continent as well.
“There’s been nothing concrete so far, but I’ve been made aware of it, put it that way. I don’t think we will lose him in the summer, as he’s just in the door and there’s more he can add to his game. But he’s got a few admirers out there with his performances last season.”
Used as a central defender in his club, Nigeria coach Stephen Keshi preferred to play Ambrose as a right back at the Afcon and he excelled in that position helping the Eagles to break down attacks as well as being a fulcrum for launching forward.