Webber clocked a time of 1 minute 39.957 seconds on the 5.554-kilometer Yas Marina course on Saturday.

The Australian came in 0.118 seconds ahead of Vettel, with Mercedes duo Nico Rosberg finishing third and Lewis Hamilton fourth.

Vettel, who has had a strained relationship with Webber this season due to their in-team rivalry, praised his colleague.

"Mark did a very good lap so congratulations to him," said Vettel, who is chasing his seventh win in a row on Sunday. "I should have done a little bit better, but I don't know if it would have been enough. He did a great job, no mistakes."

Vettel will still be keen to finish first in the Sunday race, a feat that would see him equal Michael Schumacher's record of winning seven consecutive races in one season.

It was a disappointing round of sessions for Ferrari's Fernando Alonso, who is second in the drivers' championship. Alonso is 24 points ahead of Lotus' Kimi Raikkonen, while Hamilton is behind by a further 14 points.

Hamilton's fourth place came despite the Briton spinning off track on his final lap.

Vettel assured himself of a fourth successive drivers' title last week in India, with three races to spare. At the same time, the Red Bull team secured their fourth consecutive constructors' championship.

Mercedes is vying with Ferrari for second place in the constructors' Formula One championship behind Red Bull. Mercedes leads Ferrari by 313 to 309 points.

rc/ccp (AP, dpa, Reuters)