The German manufacturer will buy 75.1 percent of Brawn GP in partnership with an Abu Dhabi investment company, with the team to be rebranded as Mercedes Grand Prix and based in Brackley.
Team principal Ross Brawn will remain in his role but the future of Button is less certain.
The 2009 Champion remains in contract talks with his current team over a new deal and while chief executive Nick Fry – who will also remain in his role – said he and Brawn would prefer Button to remain, he admitted financial constraints may prevent that.
“We have had discussions with Jenson about what we think are a sensible salary,” Fry said.
“This (takeover by Mercedes) is not going to change anything in that respect.
“The decision at the end of the day on drivers will be made by Ross principally with my help.
“We’re going to continue to run the team and it will be our decision on who is going to drive the car.”
Brawn and Button forged a close relationship during a remarkable 2009 season when Button claimed the drivers’ title while the team won the Constructors’ Championship at the first time of asking.
Despite their success it has been widely reported that the new manufacturer has already signed a deal to make German driver Nico Rosberg their new number one, with Button tipped to join McLaren as he seeks a salary increase.
Fry for one is keen for that scenario to be avoided and added: “I hope Jenson is still with us next season.
“We’ve been together for a good few years now and we have succeeded in winning the World Championship together and we want Jenson to be with us.
“But we have to recognise that Formula One is not divorced from the rest of the world.
“We have worked within a budget (and) if we spend in one area then we cannot spend in another area.
“The reason we survived as a team was that we operated in a sensible way and operated within our means and as the chief executive that is my job and we’re going to continue to do the same.”
Fry also served to play down speculation that Mercedes will look to employ an all-German team next season, with Nick Heidfeld and Timo Glock also linked to the team alongside Rosberg.
“I can confidently say that (speculation) is totally incorrect – Mercedes is an international company,” he added.
“Clearly a German driver would be nice for them but we don’t need two German drivers, that’s not the intent.”
Mercedes motorsport vice-president Norbert Haug, however, intimated that a change in personnel was on the cards, saying: “Hopefully we can announce this in the next couple of weeks.
“We will do a good job in that point of view and maybe we can cause some surprises.”
Mercedes-Benz’s deal with Brawn ushers in a slow break from their current ties with McLaren, who will buy back the German manufacturers’ 40% shareholding by 2011.
Mercedes will, however, continue to supply engines to McLaren until 2015.
McLaren will continue to be branded as Vodafone McLaren Mercedes.