Welcome to qualifying for the Singapore Grand Prix, the cars are being fired up and we are just 25 minutes away from the start of Q1.

Red Bull topped all three practice sessions and it looks as though they might dominate this weekend. Vettel has been very quick but we could still see Ferrari's Alonso spring a surprise.

Even if Red Bull are on top, there will still be an almighty battle between Vettel and Webber as the two team-mates fight for supremacy at the team and in the championship. Webber was only sixth fastest in FP3 but he didn't have the opportunity to put in a really fast lap at the end due to yellow flags at turn 18.

So there are still plenty of unknowns ahead of this qualifying session. The main one for the drivers will be over the condition of the track. A rain storm earlier today left it damp for FP3 and turn 5 was still treacherous at the end of the session.

Update from Lotus: "Tricky tyre choice for qualifying. Option should be quicker but lots of drivers struggling at the end of P3 on them"

Q1 is just minutes away and the grandstands and vantage points around this 5km circuit are now being filled.

The drivers are now being belted in and in a couple of minutes they will be on track.

The session is under way and Tonio Liuzzi leads the cars out onto the track.

Both Virgins, both HRTs and both Lotuses are out early. They are the most likely to knocked out ahead of Q2. The question is who will be going with them.

Schumacher holds a huge slide in turn two after running wide in turn one. That has ruined his first attempt but he's on the hard tyres and will take a few laps to warm them up anyway.

Liuzzi sets the fastest time so far with a 1:50.223. But the times should improve dramatically over the next few minutes.

Hamilton posts a 1:48.454 to go top of the timesheets. And Button beats that with a 1:48.254.

The track condition looks better than it did in FP3 but it is still damp in places. And obviously still difficult to drive as Buemi tags the wall out of turn 17.

Alonso clocks a 1:47.623 but that is beaten by Vettel with a 1:47.303.

Meanwhile, Hamilton is wrestling his car through the corners and is only sixth fastest.

Hamilton improves to fifth with a 1:48.296 but was in traffic.

Alguersuari has posted a good lap - 1:48.196 - to go ahead of the McLarens.

Massa has stopped on track with a suspected engine problem.

The session is red flagged. Massa hasn't set a lap time yet so will start from the back. He may as well take a new engine and the resulting penalty as he can't do any worse than that.

The car stopped right in the middle of the road and there was no way it was going to safely removed without a red flag. It's now being lifted away by the marshals and we should be back on track in a matter of minutes.

10:35 remain in this session.

Button is cooling down with plenty of dry ice in his cockpit.

The session will restart in two minutes.

Hulkenberg is straight back on track in the Williams as the pit lane opens again.

Turn five still has a distinct sheen and must still be very slippery.

Lotus update: "Jarno not happy with balance, Heikki's third lap would have been quicker but got traffic, Klien"

Latest reports suggest it was a gearbox problem and not an engine failure in the back of Massa's car.

Schumacher has jumped out of his car and gone straight to the back of the garage. I can only presume there is a problem with the car or he has been caught short. He is currently seventh but not necessarily safe.

Alonso and Webber are back out on track. Vettel is almost certainly safe but might go back out to get a bit more running in the conditions.

So we should see the drivers of the new teams drop out in this session alongside Felipe Massa.

Kubica sets a decent lap with a 1:47.657.

Vettel's best time yesterday was a 1:46.660 so we still haven't seen a better lap time today.

Senna has spun his HRT as Alonso goes fastest with a 1:46.541. Senna is currently 0.2 seconds off his new team-mate Klien and just pushed a little bit too hard in the slippery turn five when he made his mistake.

Virgin is leading the new team battle but it is expecting Kovalainen to put in a quick time: "You have to expect KOV to put one more blinder in..."

Senna finishes his last lap but is about 0.9 seconds slower than Klien who recorded a good lap on his first qualifying session back in F1.

Kovalainen did put in one more lap to split the Virgins, but Glock is still the quickest of that group of new drivers.

Anmol asks: "I was just wondering…why couldn't Massa just replace his gearbox and come back out and set a lap?"

His car stopped on track and as soon as the car has to be pushed off the circuit he is officially out of qualifying. What's more, the car was on the other side of Singapore and to get it back and sort the problem would take a long time.

Vettel is ready at the end of the pit lane on hard tyres and away they go to start Q2.

Kubica is out on soft tyres for his first Q2 run.

Alonso is on hard tyres but is in heavy traffic. He asks over the radio whether he has to change the engine mapping, but doesn't get a clear response.

Liuzzi lost the rear end into the turn 10 chicane and he was lucky to miss the kerbs where Sutil broke his suspension yesterday.

Petrov has broken the right rear suspension of his Renault against the wall on the exit of turn five.

Alonso is told to complete one banker lap before returning to the pits for the team to check the engine.

Hamilton goes fastest of all with a 1:46.042. Alonso is back in the garage now with frantic work going on. He is currently eighth but could still be knocked out.

Alonso is heading back out after resetting the telemetry on that Ferrari.

At the moment it looks as though the two Saubers and two Force Indias will drop out. Schumacher is also likely to drop. Alguersuari is looking quick and might just sneak through to Q3.

Alonso confirms that the car is OK. He is told that he needs one clean lap now. He is out on the soft tyres and pushing hard.

Alonso goes fastest with a 1:45.909, a very quick lap but we haven't seen the Red Bulls on soft tyres yet.

Vettel is now out on the softer compound.

And Vettel tops the timesheets with a 1:45.561, over 0.2 seconds up on Alonso.

Schumacher is fighting very hard to try and secure a place in Q3. He gets ninth place.

Hulkenberg and Alguersuari are out, Schumacher and Kobayashi look safe.

Bad day for Force India as they qualify 16th and 17th.

Hulkenberg slams his helmet against the Williams garage wall as he gets out of his car. He got knocked out and will start 12th and the pressure is clearly getting to him. His team-mate Barrichello is through to Q3.

Button leads the cars out for the final session of qualifying. It's very tightly poised and we could still see a non-Red Bull car on pole.

Kubica and Kobayashi haven't gone out and will just complete one Q3 lap.

Vettel is quicker than the rest through sector 1. Hamilton is much faster than Button so far on this lap.

Hamilton clocks a 1:45.571 but Alonso is quicker with a 1:45.390.

Hamilton really attacked the kerbs at the turn 10 chicane. Vettel messed up his middle sector but will get one more attempt at pole.

Alonso returns to the pits for another brand new set of soft tyres.

Kubica is still in the garage waiting for his single run. Barrichello has posted a brilliant time to go fifth fastest at the moment. The Williams driver will need a very quick turn around to get him out. And they do a racing pit stop to get him out again, which meant his first lap was with two runs worth of fuel.

All 10 cars are on the track now, the pressure is on as they are trying to find a big enough gap in the traffic.

Button will be the last man to cross the line and start his final lap.

Vettel starts his lap ... and he nearly runs wide at turn five but holds it all together to go 0.1 seconds faster than Alonso in the first sector.

Hamilton and Webber do not improve on their first sector times.

Vettel can't beat Alonso, he's slower. Alonso is also slower than his time.

Button gets fourth to beat Webber but its Ferrari and Alonso on pole.

Vettel just tagged the wall on the Esplanade Bridge but it won't have cost him too much time.