Red Bull U-turn on Sebastian Vettel Ferrari F1 test

The four-time world champion is leaving Red Bull for the Scuderia after spending his entire racing career as a protege of the energy drink company.

He was expecting to join Ferrari for the Yas Marina test next week, but Red Bull has changed its mind because it fears he would take secrets with him.

"Yes," the German replied when asked if Red Bull had blocked the test.

"It is a shame, especially because initially I was allowed and then I wasn't. It is what it is.

"I don't know [why it happened]. All of a sudden something changed, I think as far as I understand, I don't know.

"The technical people were panicking a little bit, afraid I might take some secrets..."

Vettel ended his final qualifying session for Red Bull sixth, behind team-mate Daniel Ricciardo, meaning he ends a full F1 season without a pole position for the first time in his career.

He believes the cooler track conditions as darkness fell upset the balance of his RB10.

"The car was too disconnected," he said. "We seemed to lose the balance compared to practice, which we are not sure why. On top of that we lost some time down the straights.

"We were hoping that the fact the track cools down when the sun goes down will help us, usually it did. It helps our balance of the car. But where everyone seems to pick up one second, we didn't pick up anything.

"I had a quick look - we lost also some time down the straights. [I was] struggling with the rear basically for the whole lap much more than we were in practice."