Mercedes and engine customer Williams have both fired up their 2017 cars for the first time ahead of pre-season testing in just over three weeks time.
Championship winners Mercedes will unveil its 2017 car, the W08 Hybrid, on February 23 during a shake-down at the Silverstone circuit with drivers Lewis Hamilton and Valtteri Bottas.
The team released a short video clip of their latest power unit firing up in the factory.
Williams meanwhile confirmed on Twitter that their car successfully fired up on Wednesday for the first time. The Grove outfit have yet to confirm their launch plans.
"Music to our ears! We successfully fired up the FW40 yesterday and car build is progressing on schedule," the team wrote.
Williams will run rookie Lance Stroll alongside Felipe Massa, who exited his short retirement to fill the gap left by Bottas' departure.
