Lewis Hamilton and Heikki Kovalainen have both been penalised five places on the starting grid for Sunday's Malaysian Grand Prix following allegations of blocking in the qualifying session.

The pair were among the first batch of drivers to complete a second flying lap and were attempting to conserve fuel with a slow return to the pits, but BMW Sauber's Nick Heidfeld and Renault's Fernando Alonso had timed their final runs to coincide with the arrival of the chequered flag. As a result of the differing speeds on track, the latecomers had to weave their way around a gaggle of cars early in the lap, with the two silver McLarens the most visible culprits when it came to failing to make way.

"Most of the cars were already very, very slow when I was on my flying lap - just like they were parked on the circuit," Heidfeld told Britain's ITV coverage after the session, "The biggest fault was both of the McLarens, in turn four, being in the middle of the racing line. I could not take the line I wanted, especially for braking [and] I lost some time there. If you look at the times, they were very, very close, [and] I think I lost two tenths, which would be third place."

Heidfeld's team-mate Robert Kubica qualified on the front row in Melbourne a week ago, and Heidfeld had topped the Saturday morning practice session at Sepang, suggesting that BMW Sauber could be a threat to Australian winner Hamilton and McLaren.

Alonso also complained about the traffic, without naming names, in Renault's post-session report, and will also benefit from the penalties handed out to the Mclaren duo. Having qualified third and fourth respectively, Kovalainen and Hamilton will now line up eighth and ninth, promoting Toyota's Jarno Trulli and Kubica to row two, Heidfeld to the inside of row three and Alonso to seventh, behind Red Bull's Mark Webber. Timo Glock's tenth position remains unaffected by the reshuffle.

Although Kubica and Felipe Massa were also in the group, they were not singled out for punishment, ensuring that the front remains the preserve of Ferrari.

A McLaren spokesman confirmed the penalty several hours after qualifying had finished, following a lengthy stewards meeting, but said that McLaren had no intention of appealing the decision.