Fiat Vice-Chairman, John Elkann is revealed to take over the post of the group's Chairman, a source close to the matter disclosed, as the car maker convened a snap conference a day before a long-planned, six-hour strategy presentation.

In addition, the source told Reuters on Tuesday that current Chairman Luca Cordero Di Montezemolo would step down, replaced by Elkann, who represents Fiat's controlling Agnelli family.

Italian news agency ANSA posted that Sergio Marchionne will power the chief executive seat, a role he also holds at U. S. car giant, Chrysler.

Montezemolo will be a part of the Fiat board and will stick to the chairmanship of Ferrari, the company's luxury sports marquee.

"When Elkann was nominated vice chairman it was expected that sooner or later he would become chairman. It is not surprising or totally unexpected", quoted a Milan-based Fiat analyst, who asked for anonymity.

The car maker's shares traded up 3.72% at 9.89 Euros by 1053 GMT as the STOXX Europe 600 auto sector index .SXAP registered a 4.69% climb, triggered by positive results from Germany's Daimler.