Formula One qualifying will be modified to prevent the danger of drivers suddenly slowing to save fuel after their final quick laps while others are still at full speed, the governing FIA said on Friday.

A spokesman for the International Automobile Federation (FIA) confirmed the change was likely to be enforced before next week's third round of the season in Bahrain.

"Our clarification to the teams and drivers will be that cars returning to the pits having completed their flying lap or laps will be required to do so within a time that we will set," he said.

"This could be approximately 120 percent of the normal time as we do to prevent drivers going very slowly to the grid (on the pre-race formation lap) to save fuel."

Teams and drivers called on the governing body to act after last weekend's Malaysian Grand Prix threw up an obvious danger in the third and final qualifying phase.

McLaren's Lewis Hamilton [Images] and Heikki Kovalainen were penalised five places on the starting grid for impeding rivals but the safety implications caused more concern than the sanction.

The rules have changed this season, preventing the 10 drivers who take part in the final session from refuelling between the end of Saturday's qualifying and the race on Sunday.

The revised format has raised safety concerns with drivers slowing to save fuel immediately they finish while others are still at full speed.

"I clearly don't like the dangers implicit in this situation," said BMW [Images] Sauber team boss Mario Theissen at the weekend.

"The speed differentials are so great that this is a problem which we need urgently to resolve, hopefully by the next race in Bahrain."

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