The Portuguese champions are keen to keep Atsu on their books, but the player’s rejection of their latest offer will have invited Spurs, amongst other clubs, to sit up and take notice, Sky Sports reports.
The Ghana international, who will play at the Africa Cup of Nations this season, has just 18 months left on his current deal at Estadio do Dragao. Porto were hoping to increase his release clause to €30million (£24m) by agreeing a new contract.
If Atsu was to see out his contract Porto would only receive minimal compensation for his services, so they could be tempted to cash-in on him if they cannot agree a new deal with the 20-year-old.
Atsu entered the first-team fold at Porto during Andre Villas-Boas’ reign, and Tottenham have tracked his progress since the Portuguese took up the hotseat at White Hart Lane.
It is thought that Villas-Boas wants to bolster his squad during the January transfer window, with fellow Porto midfielder Joao Moutinho another potential target.
Spurs were heavily linked with the 26-year-old Portugal international in the summer, but a deal fell through and the North London side could face competition from the likes of Borussia Dortmund, Valencia and Lyon for the skilful wide-man’s signature this time around.
Porto may be reluctant to sell either Atsu or Moutinho, as they battle for the Portuguese league title with Benfica and compete in the Champions League’s knockout stages in the new year.