Kouyate, 25, joined the Hammers from Belgian outfit Anderlecht last summer, and the Senegal international quickly made himself a fan favourite at Upton Park.
The midfield powerhouse produced some dominant displays, even earning comparisons to former Arsenal star Patrick Vieira due to those impressive performances.
Now, as we enter the final day of the transfer window, it seems that Kouyate's displays with the Hammers have attracted interest - from London rivals Tottenham.
Spurs are looking for a powerful midfielder to protect their defence, and whilst The Sun report that Southampton's Victor Wanyama is still an option, they also add that Kouyate is a new target.
It's reported that Spurs believe Kouyate wants a move to White Hart Lane, and a £15m bid will be submitted before the transfer deadline - but given the rivalry between the clubs, Tottenham may find a deal for Kouyate difficult to complete in such a short space of time.
Kouyate proved last season that he can be a star in the Premier League, and he would bring the strength and athleticism that Tottenham need in the middle of the park, though given how West Ham need to sign players rather than lose them, Slaven Bilic's men will certainly be difficult to deal with if Tottenham do indeed want to sign Kouyate.