Sauber have denied that they are swapping to Mercedes power in 2014 when the new engine regulations kick in.
Next season Formula One will swap the current V8 engines for smaller turbo-charged 1.6-litre V6s.
This move could see some changes in the engine market with reports in France claiming that Sauber will be changing to Mercedes power with Force India moving in the opposite direction.
Sauber, though, have refuted the reports.
"We do not have an engine partner for 2014, not least because several aspects are still unclear with regards to the cost," a Sauber spokesman told Swiss publication Speed Week magazine
"However, the fact is that we have more than ten years working with Ferrari and the Scuderia is naturally our first point of contract."