The Spaniard has already been signed up for next year by Toro Rosso owner Red Bull, but there are rumours that the energy drink company might negotiate a trade deal in exchange for cheaper customer engines from its French supplier.
"It's false," Sainz said when asked by Vogue Espana if the rumours of a swap deal with Renault are true.
"I am mentored by Red Bull and Toro Rosso is their second team. So if they don't want me to go, I will not go."
Sainz, 22, also said that his only friend in the F1 paddock is mentor and countryman Fernando Alonso.
"Apart from him, no," he insisted.
"There are people who you get along with better or worse, but being friends is difficult. It is a very false sport and although you have to get along with everyone, mixing friends with work is not good."
Sainz currently sits 12th in the driver rankings ahead of next weekend's Malaysian Grand Prix.