2011 GP3 Series champion Valtteri Bottas and newly crowned F2 champion Mirko Bortolotti will drive for Williams in F1's young driver test, which takes place at Abu Dhabi next week.
Bottas is already the team's official test and reserve driver while Bortolotti has been given the opportunity as part of his reward for winning the title in F2, which Williams builds the cars for.
"I'm obviously really pleased that I have been given the opportunity to test in Abu Dhabi with Williams," said Bortolotti. "I will try to learn the car as quickly as possible and do the best I can for the team.
"I hope to learn lots of information from the engineers during the time I have and just enjoy it. For sure it's going to be a big day for me and I'm looking forward to it."
Bottas has driven Williams Formula 1 cars before but only in straightline testing so is relishing the opportunity of the test, which takes place from Nov. 15-17.
"I'm very much looking forward to these two days in Abu Dhabi," said the Finn. "It's something I have waited a long time for and is a dream come true.
"I have done everything I can to prepare myself for the test physically, and I have done a lot of preparation work with the team in the simulator, so I feel I'm 100 percent ready. It will be great to have a go on a proper circuit now!"