Toro Rosso will retain Italian driver Vitantonio Liuzzi for this season but the future of American Scott Speed has yet to be confirmed.
Liuzzi (left) and Speed are likely to team up once again
Team co-owner Gerhard Berger said Speed remained on pole position for the second drive at the Ferrari-powered team but nothing had been signed yet.
"Everything is fine with Tonio, he's in the car and will drive," he said.
"With Scott we still have some contractual issues to sort out. We are going to see later."
Italian Liuzzi scored one point last season for Toro Rosso, who came into being in 2006 after Red Bull bought out Minardi, while American Speed finished 20th in the drivers standings with no points.
Toro Rosso have tested three-time Champ Car champion Sebastien Bourdais over the winter but Berger only discussed his involvement as "options".
Williams and Spyker are worried because they fear our competitiveness
Toro Rosso co-owner Gerhard Berger
Berger added: "Money is not an issue. We are looking for performance.
"It is the performance that will get a driver a cockpit and not a hand waving a cheque."
Toro Rosso also started to test their new STR2 car, which will be powered by Ferrari engines instead of the Cosworths the team used last year.
The team have attracted controversy because many of their rivals expect the car to be a direct copy of the new model designed by sister outfit Red Bull, which would contravene F1's regulations on custom-built cars.
The car they tested did indeed bear a striking resemblance to the new Red Bull.
But Berger, who won 10 Grands Prix during his racing career, insists the new Toro Rosso will be within the legal requirements.
"In our view we are 100% fine," he said. "It is basically Williams and Spyker who are worried, and I know the reason for that - they fear our competitiveness.
"If Frank Williams were more in front he would not care for a moment. But naturally our aim will be to close the gap to them."