Raikkonen, who finished third at the last race in Bahrain, set a time of 1:19.886 late in the session to push Michael Schumacher down to second and Alonso, the last driver out, could not better his time.
Alonso has won the last two races from pole position and he will be in with a strong chance of securing a third top spot after setting a time just 0.003 seconds slower than Raikkonen to claim second.
Schumacher, who qualified on the front row for the last race in Bahrain, led for most of the session after going out early but he was forced to settle for third after being bumped down the order.
His World Champion Ferrari team have struggled in the first three races and are hoping for a stronger performance in this weekend's event after undertaking a mammoth testing stint in the last three weeks.
Mark Webber finished fourth for Williams but was more than half a second off the lead pace and last year's pole position winner Jenson Button, boosted by a much-improved BAR-Honda this weekend, finished fifth.
Italian Jarno Trulli, of Toyota, finished sixth fastest after a disappointing run and Brazilian Felipe Massa, of Sauber, claimed seventh place.
Alex Wurz, who is deputising for the injured Juan Pablo Montoya this weekend, managed eighth fastest time, 0.746 seconds off the pace of his session-leading teammate Raikkonen.
German Nick Heidfeld made it two Williams drivers in the top ten when he slotted into ninth place and BAR-Honda driver Takuma Sato, of Japan, completed the top ten positions.
Minardi suffered from limited running with their new PS05 car leaving Christijan Albers and Patrick Friesacher to settle for the bottom two places once again, with the latter more than six seconds off the pace.
Giancarlo Fisichella was one of the first drivers out but made a mistake on his lap that cost him time and Michael Schumacher was the early pace setter with a time of 1:20.260, pushing early leader Wurz down to second.
Button then demoted Wurz further as he set a time 0.204 seconds slower than Schumacher and Barrichello could not get close to his teammate, finishing 0.632 seconds off his pace.
Former World Champion Jacques Villeneuve finished within eight tenths of a second of Schumacher but still lost out to Massa, who slotted into third, 0.333 seconds off the lead pace.
Webber then slotted into second, 0.182 seconds off Schumacher's pace and almost four tenths faster than teammate Nick Heidfeld, before Raikkonen shot ahead of Schumacher with just Trulli and Alonso left to run.
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