"Ford will withdraw from @OfficialWRC as title sponsor after 2012. #FordWRC thanks its fans, drivers and many partners for their support," a Ford tweet read.
Talks about keeping the Ford cars, driven by the likes of third-placed Finn Jari-Matti Latvala, in next year's championship but without a works presence are ongoing.
The M-Sport organisation has run Ford's factory outfit since 1997, winning the manufacturers' championships in 2006 and 2007.
Rallying has a suffered a series of blows this year, notably Citroen's multiple world champion Sebastien Loeb saying he will not compete for the title next year as he scales back the number of rallies he will race in.
A group involving energy drinks firm Red Bull will take over as global promoters next year after problems at the start of this season when the parent company of then promoters North One Sport went into administration.