Britain's George Russell seized the first pole position of his Formula One career with a stunning qualifying lap in Hungary as Mercedes found surprising speed and swept past fancied Ferrari.

Russell, nicknamed 'Mr Saturday' when he was at lowly Williams for his qualifying performances, hit the sweet spot just when it mattered most to set up a real chance of a first win on Sunday.

"We'll be absolutely going for it. Victory is what we're going for," he said.

With Red Bull's runaway championship leader Max Verstappen suffering late power problems that left the Dutchman 10th on the grid, the Ferrari drivers had looked set to sweep the front row.

Carlos Sainz had taken provisional pole for the Italian team and Charles Leclerc then went second fastest with his last flying lap before Russell, behind them, changed everything.

"Yesterday was probably our worst Friday of the season," said Russell, who was "absolutely buzzing" on a special day for the 24-year-old and the reigning champions who had not been on pole since last season.

"Everybody last night was working so hard, we didn't really know what direction to go in.

"Then that last lap, I got round turn one, mega turn one ... turn two was mega and the lap time just kept on coming. I came across the line, looked at the screen and saw we went P1 and that was an incredible feeling."

Russell was second fastest after the first flying laps, but nearly half a second down on Sainz who ended up as surprised as anyone.

Asked if Mercedes were back in business, Russell said laughing: "I don't know. We need to look into it and understand where that came from today. There's a few ideas we have."

Seven-times world champion Lewis Hamilton, winner a record eight times in Hungary, will start in seventh and said he had suffered a problem with his Mercedes's drag reduction system.

"I was feeling great, pole or front row was definitely there for sure," said the Briton, who was fastest in the first phase of qualifying.

"It would have been awesome to get a front row for the team but these things happen."

Verstappen, 63 points clear of Leclerc at the top after 12 of 22 races, locked up and ran wide on his first flying lap that left him languishing in seventh.

He then complained over the radio of a lack of power when he went out for his final attempt. The champion tried in vain to reset the car, telling the team that nothing was working, and aborted the lap.

"I don't think it's a big issue but something we couldn't solve on track. It's very unfortunate," he said.

Mexican team mate Sergio Perez failed to make the top 10, qualifying 11th at a track where overtaking is always tricky.

He also had a lap deleted for exceeding track limits, only for it to then be restored.

McLaren's Lando Norris qualified fourth alongside Leclerc, with the Alpine pairing of Esteban Ocon -- last year's surprise first time winner in Hungary -- and Fernando Alonso filling the third row. The Alpine pair were split by just 0.060.

Alfa Romeo's Valtteri Bottas will line up alongside Hamilton, his former Mercedes teammate, with McLaren's Australian Daniel Ricciardo next to his ex-Red Bull partner Verstappen.

The session was dry and cool after a wet final practice threw up a freak timesheet, with Williams' Nicholas Latifi on top for the first time.

Normal service was resumed in qualifying, with Latifi slowest again.