World champion Verstappen is under contract to Red Bull until the end of 2028 but there are clauses in his contract that could see him leave under certain circumstances.
Briton Russell, who has been with Mercedes since before he was in F1 and won two races last year, said he was confident the team would stick with him.
“We have had such a long-term relationship and so much trust between one another and we are focused on getting Mercedes back on top and trying to win races and championships,” Russell said.
“Performance speaks, so from my side there is no pressure. I have no doubts about myself and everything falls into place when the timing is right. We have bigger fish to fry right now, which is getting us back on top.”
Formula 1 is changing its technical regulations for next season, introducing new rules for both cars and engines. That makes it difficult for any driver to predict which will be the most competitive team from 2026.
Red Bull potentially has greater uncertainty over it as they have set up their own engine facility to build a new power-unit for next year in partnership with Ford.
Mercedes has been the standard-setter in F1 engines since the current hybrid rules were introduced in 2014.
