Tottenham Hotspur and Sporting Lisbon are reportedly still £10m apart in their valuation of Pedro Porro.
The North London club are interested in the right-back as a result of Emerson Royal and Djed Spence's struggles, with first-choice Matt Doherty turning 31 years old just three days ago.
Portuguese outlet Record reports that Antonio Conte's side have made an opening offer of £29m plus bonuses, however, Sporting are holding out for their £39m asking price.
The 23-year-old has impressed Conte in two appearances against Tottenham in the Champions League group stages, and the Italian is putting pressure on his board to conclude a deal as soon as possible, according to the report.
The Lilywhites face competition for the Portugal international's signature from London rivals Chelsea, with Graham Potter interested in the player as competition for Reece James, who has been plagued by injuries recently.
The one-cap international has featured 23 times in all competitions so far this season, scoring two goals and assisting 10.
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