Sporting CP are threatening to pull out of the sale of Pedro Porro to Tottenham.
The Spain fullback was expected in London this morning for a Spurs medical after terms over a fee had been agreed on the weekend.
However, TMW says Sporting are now making new demands from Spurs.
Sporting want to change the terms of the deal and the transfer is now under threat.
The big problem for Tottenham and Porro is that the fullback's contract doesn't carry a buyout clause.