Sebastian Vettel has kept his pole position for Sunday's F1 Grand Prix of Japan at Suzuka, after a tense three-hour session with the race stewards over an incident in Q3 where it was suggested that he'd impeded Fernando Alonso

Vettel claimed his 34th career pole as Red Bull posted their first front row lock-out of the season after qualifying in Japan, but that was thrown into doubt after Vettel was ordered to report to the stewards office after the session ended to explain his driving in Q3 which appeared to impede Ferrari's Fernando Alonso.

Vettel had slowed after encountering the yellow flags for Kimi Raikkonen's spin, which were withdrawn by the time Fernando Alonso came through. The Ferrari then rapidly closed up on the back of the Red Bull which was on the racing line into the chicane: Vettel ran wide to allow Alonso to pass, but still briefly held up the Ferrari in the process.

The meeting with the stewards went on for almost three hours and was described by some observers as being "heated" before word came that Vettel would not lose grid places for the start of this weekend's Grand Prix, even though the official notification from the stewards said that he had been deemed to have impeded Alonso at turn 16. That was described by the stewards as "an incident as defined by Article 16.1 of the FIA F1 Sporting Regulations."

Instead of a penalty, Vettel was merely reprimanded - with the stewards adding that the reason for the reprimand was "self-explanatory" without elaborating further.

Earlier, Toro Rosso's Jean-Eric Vergne had been handed a three-place grid penalty after having been found guilty of impeding Williams' Bruno Senna at the same place as Vettel and Alonso had their own incident. In this case, Vergne had continued on the racing line through the chicane before giving way, which is what made the difference in the stewards' eyes with regard to the differing sanctions that were levied, especially as the Vergne incident cost Senna a chance to progress to Q2.

Jenson Button and Nico Hilkenberg also have five-place grid penalties after McLaren and Force India were forced to change their gearboxes heading into the race. And Michael Schumacher will be forced to the back of the grid by a ten-place grid penalty for crashing into Vergne during the Singapore Grand Prix two weeks ago.

Initially it was thought that Sauber's Kamui Kobayashi might also be handed a penalty and lose his third place on Sunday's grid after setting his fastest qualifying lap at a time when there were local waved yellows at the exit of Spoon for Kimi Raikkonen's Lotus which was temporarily stuck in the gravel trap.

However, Sauber presented telemetry supporting their contention that the Japanese driver did not set a fastest time through the specific part of S2 at the exit of Spoon after Raikkonen spun off, and had not used either DRS or KERS. After reviewing the information, the stewards decided to take no further action against Kobayashi.