Newcastle have rejected a bid of £14million from Paris St Germain for Yohan Cabaye.
It is understood the big-spending French club has finally formalised its interest in the former Lille midfielder, but that the offer was swiftly rebuffed.
Speculation has been mounting for weeks that PSG would make a move for the France international this month despite manager Laurent Blanc's earlier indication that they would not.
However, amid rumours that Manchester United are ready to battle them for the 28-year-old's signature, they have fired the initial shot in a battle which could run until the end of the winter transfer window.
Arsenal tested the water during the summer with a £10million bid which came nowhere near matching Magpies owner Mike Ashley's valuation of arguably the club's most prized asset.
Newcastle's asking price is understood to be well in advance of £20million and whether PSG come back with a further approach which prompts Ashley to think about selling remains to be seen.
The current offer would represent a handsome profit on the £4.3million the Magpies paid Lille for Cabaye in July 2011.
However, having emerged from the furore sparked by Arsenal's interest in August, he has once again become the linchpin of Alan Pardew's team and the Magpies boss is desperate to retain his services.
The 52-year-old, who has spent much of the last two transfer windows insisting he does not want to sell any of his leading players, nevertheless knows there is a point at which a decision would have to be made, and that that would not be down to him.
But just as it took a cheque for £35million to persuade Ashley to part with striker Andy Carroll in January 2011, so too will it require a similarly outrageous offer this time around.
Cabaye has recently spoken of his contentment on Tyneside and there seems to be no particular appetite on either side to engineer a move this month.
Pardew has repeatedly warned that he may not enjoy the same lofty status at a bigger club, and with a trip to the World Cup in Brazil to come this summer, the midfield playmaker knows he needs to be playing regularly to secure his place in the national team.
However, the manager now faces a potentially uncomfortable final few days of the window waiting to see if PSG, or indeed anyone else, are prepared to up their bid.
Carroll, of course, left St James' Park on deadline day, leaving Newcastle no time to sign a replacement, and contingency plans have been drawn up to avoid such an eventuality once again.
Montpellier's Remy Cabella, while not a direct replacement, is firmly in their sights, although the French club are insistent that he will not be sold this month.
Borussia Monchengladbach striker Luuk de Jong too remains a target, but Ashley and director of football Joe Kinnear are determined only to do business if it makes financial sense.