Sauber have denied claims their planned investment from a new Russian backer is at risk.
German media reports on Tuesday said the board of Russia’s National Institute for Aviation and Technology had voted against a plan to invest in the Swiss team.
Sauber told Autosport their plans remained “on a solid footing”.
However the team insisted NIAT had never been expected to invest in the team. In addition to the arrangement with NIAT announced last month Sauber confirmed the Investment Cooperation International Fund and the State Fund of Development of North-West Russian Federation were also involved in the project.
Sauber added that plans for 17-year-old Russian Formula Renault 3.5 racer Sergey Sirotkin to join the team were proceeding.
“The contract with driver Sergey Sirotkin is active, and he will commence preparations next week – after Formula 1’s obligatory holidays. In addition contracted payments to the team have already been made.”
Sauber added they were “bewildered by the ease with which various media have published falsehoods and rumors”.
The team admitted it was facing financial problems during the German Grand Prix weekend after reports claimed they had fallen behind on bill payments. Sauber has been in F1 since 1993, and was owned by BMW between 2006 and 2009.