US F1 are poised to appoint Adrian Valles as their second driver ahead of their debut campaign in Formula One.

The Charlotte-based team, who recently signed Argentinean Jose Maria Lopez, look set to confirm Valles next week.

The 23-year-old Spaniard from Alicante, who was previously a test driver with Spyker in 2007, won last year's Superleague Formula title with Liverpool

Speaking to local media, a coy Valles said: "I'm sorry, I can't talk. I just hope things don't go wrong."

Should US F1 sign Valles, he will be the fourth Spaniard on the grid for 2010 along with Fernando Alonso at Ferrari, Pedro de la Rosa of Sauber and Toro Rosso's Jaime Alguersuari.