Kimi Raikkonen's management is believed to be in talks with Mercedes GP about a race seat in 2010.
With McLaren signing Jenson Button, the Finn's manager Steve Robertson said on Wednesday that Raikkonen, 30, would take a year off in 2010 and go rallying instead.
But with Brawn/Mercedes now needing a driver to pair with Nico Rosberg, rumours quickly emerged that Raikkonen is an option.
Brazil's O Globo went as far as to report that a deal with the Brackley based team is a certainty, citing the information of the authoritative commentator at SporTV, Lito Cavalcanti.
He said an agreement was finalised on Wednesday.
Robertson would not confirm the news but he did not rule out the possibility of a Mercedes deal, amid reports in Spain's Diario Sport that Raikkonen is in talks with Citroen about a World Rally Championship seat.
To the German news agency SID, Mercedes' Norbert Haug would not shed any light.
"We want to have the best possible lineup and there are still some very capable drivers on the market. There will of course be speculation," said the German.