May 25 (F1Plus / GMM) Williams' move from Renault to Mercedes power for 2014 appears set to be announced.
Earlier in the Monaco Grand Prix weekend, GMM reported rumours from the Monaco paddock that the deal for the British team could be on the cards, because Renault was charging multiple millions more than Mercedes for a turbo V6 package.
"The decision is made and it will be announced this weekend in Monaco," said Swiss newspaper Blick's veteran correspondent Roger Benoit.
Germany's Michael Schmidt, of Auto Motor und Sport, is reporting similarly.
The Mercedes link is also an obvious one for Williams, with team co-owner Toto Wolff now the German marque's executive director, and Wolff's wife Susie the Williams test driver.
Mercedes would become Williams' fifth different engine partner since 2005, after BMW, Cosworth, Toyota and Renault.
Renault engines have been extremely successful over the past few seasons, powering Red Bull to three consecutive Drivers' and Constructors' Championships, and delivering wins for Lotus in Abu Dhabi last year and Australia this season. But Williams have not been able to produce the same performance as their rivals despite having the same engines.
Mercedes engines have not won a championship since Jenson Button and Brawn dominated 2009. But the early rumours suggest that Mercedes power could be the way to go for the new V6 turbo formula that starts at the beginning of 2014. Williams could, as a result, be eyeing a return to the top with a new engine partnership.