The Scottish champions had an offer of £4.5million plus add-ons turned down last month.
And Brendan Rodgers has made it clear that he wants to sign the Irish international on a permanent basis after the 23-year-old scored nine goals — including a late winner in the Scottish Cup final win over Rangers — during a successful loan spell in the second half of last season.
Idah was a big hit during his loan spell at Celtic last season and is keen on a return to the club
Norwich City boss Johannes Hoff Thorup has welcomed the striker back into the fold at Carrow Road after he was disciplined for missing a flight to a pre-season friendly against Hoffenheim.
However, Idah is keen to return to Glasgow and sources at the English Championship club have confirmed to Mail Sport that Celtic have come back in for the striker and that discussions are ongoing.
It’s believed that an overall package somewhere between £6m-£8m would persuade the Canaries to sell.