It is often speculated that the German carmaker will up its current 40 per cent stake in the Woking based team, which is also owned by the Kingdom of Bahrain (30pc), Ron Dennis (15pc) and Mansour Ojjeh (15pc).
Asked about buying the team outright, Mercedes' competition chief Haug answered: "That is definitely an option, but not in the economic situation of the moment."
In interview with the German newspaper Die Welt, he insisted that "efficiency and cost saving" is instead at the top of the priority list.
Amid reports Heikki Kovalainen's seat at the team is in doubt beyond 2009, meanwhile, Haug admitted Mercedes is interested in young Germans Nico Rosberg and Sebastian Vettel.
"Before we signed Heikki we spoke with both but they had contracts that we of course respected. For the future I don't want to exclude anything," said Haug.