Britain will have four drivers on the Formula One grid next season, after Ferrari reserve driver Ollie Bearman signed for Haas.
The 19-year-old will drive the car at Silverstone on Friday ahead of the British Grand Prix, his third practice run with the team.
Bearman became the youngest British driver in F1 history with his debut in Saudi Arabia as a replacement for Carlos Sainz, when the Spaniard had his appendix removed. He finished seventh - two positions ahead of seven-time world champion Lewis Hamilton.
"It's hard to put into words just how much this means to me," he said after the multi-year deal was announced. "To say out loud that I will be an F1 driver makes me immensely proud."
Haas team owner Gene Haas said: "I'm pleased we've been able to give Oliver Bearman this opportunity to drive full-time in Formula One - he's undoubtedly an exciting rookie prospect, not just based on what he showed in Saudi Arabia but also through his time developing his relationship with our team.
"I'm personally excited to see how he grows as a driver, and we look forward to seeing him deliver for Haas next season and beyond. This is an exciting time for the team."
