Celtic have turned down an ‘improved’ bid of £5million plus from Norwich City for striker Gary Hooper.
Canaries manager Chris Hughton has made Hooper a primary target this month as he looks to bolster his striking options.
Norwich had already seen a bid for the 24-year-old turned down by the Bhoys.
Lennon has warned Hooper that the offer of a bumper contract extension at Celtic will be removed from the negotiating table if the striker refuses to sign it this month.
Hooper scored twice in Celtic’s 4-0 win over Dundee United and Lennon again reiterated his desire to hang on to the striker, whose current contract expires in 2014.