Robert Kubica will stay in the World Rally Championship for the 2014 season and move into the top class with an M-Sport-prepared Ford.
The Pole won the WRC2 title in his first year of international rallying this season, but had been uncertain whether to continue on the stages or switch back to circuit racing.
He has now sealed a deal to do the full 13-round 2014 campaign with Malcolm Wilson's organisation, running under the Lotos World Rally Team banner.
"I am thrilled that Robert will be contesting next season in a Fiesta," said Wilson, who had made clear his desire to sign Kubica in recent weeks.
"Since he burst onto the WRC scene earlier this year, we have been very keen to have him on-board and I think that we can expect some great things from him in 2014.
"You only have to look at the way Robert prepared for the 2013 season to see what it all means to him.
"He has a desire and a hunger which you don't see in many drivers and I truly believe that M-Sport can offer him all the right tools to move forward in rallying."
Kubica tested an M-Sport Ford last summer when he was preparing for his motorsport comeback as he recovered from the devastating injuries he suffered in his rally crash in early 2011.
He outpaced then factory drivers Petter Solberg and Jari-Matti Latvala but ultimately opted to go with Citroen for this year, contesting a mixed WRC and European Rally Championship programme.
Having clinched the WRC2 title, Kubica moved up to Citroen's World Rally Car for the season finale in Wales, but crashed twice during the event.
M-Sport will also field Mikko Hirvonen and Elfyn Evans under its own banner in 2014.
2014 WRC driver line-up so far: Volkswagen Sebastien Ogier, Jari-Matti Latvala, Andreas Mikkelsen Citroen Mads Ostberg, Kris Meeke, Khalid Al-Qassimi* M-Sport Ford Mikko Hirvonen, Elfyn Evans, Robert Kubica Hyundai Thierry Neuville, Dani Sordo*, Juho Hanninen*, Chris Atkinson* * Partial programme