Sources: Ajer fuming after Celtic board's transfer U-turn
Kristoffer Ajer is furious at Celtic chiefs after they U-turned on letting him go for £15million this summer, Football Insider understands.
The club had issued agents with a £15m mandate for Ajer's sale as they looked to find a buyer ahead of the 31 August cut-off.
But the Celtic board have now changed their mind on the centre-back's value and a source has told Football Insider they have upped the asking price to £20m.
That is said to have left the Norway international, 23, furious as he looks to quit Parkhead after five years.
Brentford were convinced they would have their £15m offer including add-ons accepted by Celtic after previous bids from Norwich City and Bayer Leverkusen had been knocked back.
But the Scottish club's change of stance leaves Ajer's future up in the air.
He has been told by the club he can leave this summer if their valuation is met.
Ajer has made it clear he wants to quit Celtic with a year left on his contract and is keen to play in a top European league, preferably south of the border.
The club's change of stance seemingly ends the chances of signing a new defender ahead of the 15 July deadline for the Champions League qualifier against Midtjylland.
With Ajer not involved yet in pre-season, it leaves Celtic almost certain to field a second-string defence that threatens their prospects of progress to the next round.
Ajer wants to quit after 176 appearances for the club, 46 of which came last season.