Esteban Ocon has emerged as a serious contender to switch to Renault in 2019.
It is believed that he is the main candidate should Red Bull rescind its 'loan' to the French team of Carlos Sainz.
Frenchman Ocon, who currently drives for Force India, is himself under contract to the Mercedes development programme.
"I do not think there is any agreement with Renault, in fact we have the option of staying with him," Force India's Otmar Szafnauer said at Hockenheim.
Yet Mercedes's Toto Wolff thinks a Renault seat is a possibility for Ocon.
"Esteban is doing a very good job," he told Le Figaro.
"He has a lot of options, which is very good for him. Now we must choose what is the best for him. Renault is certainly one of the possibilities."
Rumours are linking Lance Stroll and Robert Kubica to Force India for 2019, with Sergio Perez possibly moving to Haas.