A report yesterday afternoon claimed that Liverpool, Swansea City and Sunderland were keen to sign the Nigerian international during the summer.
Despite refusing to confirm which clubs had made their interest known, Lennon conceded that the 24-year-old has a number of admirers.
"I hope we won't lose Efe in the summer as he's just in the door and there's more he can add to his game, but he has got a few admirers out there with his performances this season," Lennon is quoted as saying by ESPN. "There's been nothing concrete, but I've been made aware of it, put it that way.
"There is definite interest from top teams in different countries. He's been a great signing for us."
Ambrose joined Celtic in 2012 from Israeli outfit Ashdod.