Barcelona: Mercedes driver Nico Rosberg set the fastest time in final day testing Sunday at the Circuit de Catalunya outside Barcelona with a fastest lap time of 1min 23.168sec ahead of Russian Lotus Renault driver Vitaly Petrov.
Petrov was almost 0.3sec slower at 1:23.463 while former McLaren world champion Lewis Hamilton was third fastest in 1:23.858.
German world champion Sebastian Vettel had been fastest out of the blocks on Saturday in timing 1min 23.315sec, ahead of young Spaniard Jaime Alguersuari in a Toro Rosso (1:23.519) with 2009 world champion Jenson Button left trailing in his wake in 1:24.923 in his McLaren.
The new season is set to start on March 13 in Manama, but Formula One chief Bernie Ecclestone said earlier that the Bahrain Grand Prix could be moved to a later date in the calendar if pro-democracy demonstrations lead to it being postponed.
The curtain-raiser is in some doubt following days of unrest and clashes between the army and anti-Government demonstrators.
The unrest in the small Gulf state is part of a wave of protests that have rippled across North Africa and the Middle East since the revolt that ousted Tunisian president Zine El Abidine Ben Ali in January.
Asked when a decision on the race would be made, Ecclestone told BBC 5 Live`s Sportsweek programme: "Probably Tuesday.
The GP2 Series race scheduled to take place in Bahrain this week has already been cancelled after pro-democracy protests that have led to deadly clashes with police.
Fastest testing times Sunday:
Nico Rosberg (GER/Mercedes) 1:23.168
Vitaly Petrov (RUS/Lotus Renault) 1:23.463
Lewis Hamilton (GBR/McLaren) 1:23.858
Pastor Maldonado (VEN/Williams) 1:24.815
Mark Webber (AUS/Red Bull) 1:24.995
Jarno Trulli (ITA/Team Lotus) 1:25.454
Sergio Perez (MEX/Sauber) 1:25.557
Adrian Sutil (GER/Force India) 1:25.720
Sébastien Buemi (SUI/Toro Rosso) 1:26.155
Felipe Massa (BRA/Ferrari) 1:26.508
Timo Glock (GER/Virgin) 1:26.598
Giorgio Mondini (SUI/Hispania) 1:28.178
Daniel Ricciardo (AUS/Toro Rosso) 1:28.329
Narain Karthikeyan (IND/Hispania) 1:30.722