The Swiss, 25, has been competing in the US since 2006, and for the past four years has contested the IndyCar series, taking her maiden podium finish on the streets of Houston in the closing stages of the 2013 campaign.

She joins Sauber with a view to gaining a super licence and securing a seat on the 2015 Formula 1 grid, and is expected to undertake on-track testing, simulator training, as well as mental and physical preparation.

"This is a major step towards me achieving a life-long dream and I'm so happy to have the opportunity to take this step with such a great team," said de Silvestro.

"The Sauber F1 Team is a team with a legacy and the only Swiss team in Formula 1, which I think makes this even more exciting.

"I can't thank Monisha Kaltenborn and Peter Sauber enough for their support and belief in my abilities and for giving me this chance. I'm thrilled to have this extremely unique platform on which to prepare myself to take on the challenge."