Tottenham will enter talks with Sporting CP today about Pedro Porro and Marcus Edwards.
The Daily Mail says Sporting have so far been unwilling to sanction any transfer unless the players' buy-out clauses are met.
Porro, 23, has a £40million clause while Edwards, the former Tottenham trainee, has a £52m clause but Tottenham still hold a 50 per cent sell-on as part of his previous transfer.
Spurs have been left thin in attack after injuries to both Richarlison and Dejan Kulusevski, with just Harry Kane and Son Heung-min left of their first-choice options.
Spurs were previously thought to have cooled their interest in Porro, who was formerly on the books at Manchester City, although the defender failed to make a senior appearance for the Cityzens.