According to Sky Italia (translated by GFFN), they are in talks to sign the player along with Inter Milan and Manchester United.
Slimani is on loan at Monaco right now but he has lost his starting berth and therefore he is keen on leaving the French club halfway through the loan deal.
He wants a move to the Premier League and it will be interesting to see if Spurs manage to sign him before the window closes.
Tottenham need to bring in a striker and Slimani could be a handy option for Mourinho.