The planned final round of this year's Champ Car World Series has been cancelled for financial reasons, reducing the season to just 14 events and joining China on the list of events postponed or abandoned this year.

Although Champ Car has yet to confirm that the axe has fallen on one of its two new showcase US events, a statement published on the Grand Prix Arizona website confirmed that the 2 December finale had bitten the dust after failing to find corporate backers.

"After nearly two years of planning and preparing for Grand Prix Arizona, the organisers of this Champ Car race have determined that it is no longer viable and are therefore cancelling the event for 2007," the statement read.

"An event of this magnitude requires considerable corporate support and, though we did establish some outstanding partnerships, there were simply not enough of these to create economic viability," said Dale Jensen, owner and managing member of the sports property, "On behalf of my partner, Brad Yonover, and our staff that has worked so hard on this project, we thank everyone throughout the community - and in particular the city of Phoenix - for their tremendous support along the way. Unfortunately, current economic turmoil and the impact it has had on our sponsors precludes us from being able to produce the calibre of event we had envisioned."

Phoenix's downfall means that the 2007 campaign will end in Mexico City on 11 November, while plans to run a non-championship Champ Car Atlantic race now need to be revisited. Assen this weekend will be the first of three races bringing the season to a close as opposed to the originally envisaged five, with the planned race at Zhuhai also having been cancelled.

Jensen indicated that the decision would have no effect on the 'sister' Vegas Grand Prix, which is scheduled to start the 2008 season next April. Fans that purchased Grand Prix Arizona tickets directly will be automatically entitled to a full refund, while those purchasing via Ticket Master should contact the outlet of purchase.