Ford, Land Rover, Volvo amongst covered brands.

Sirius Satellite Radio has extended its exclusive pact with Ford through September 2011, with an option for Ford to also offer competing satcaster XM Satellite Radio in 2009 -- but with a caveat.

Earlier this year, Ford and Lincoln Mercury announced plans to target up to 21 vehicle lines for factory installation of Sirius over the 2006 and 2007 model years and said that they expect to generate up to one million Sirius subscribers over the two model-year period. Nearly 90% of Ford and Lincoln Mercury vehicles will have Sirius as a factory installed option for the 2008 model year. Factory installed volumes are expected to significantly increase.

Sirius says that beginning in January 2009, Ford may elect to become "nonexclusive" under its agreement with Sirius, “in which case Ford would forfeit all future economic benefits, which could be significant.”

All Ford brands in the U.S. -- Ford, Lincoln Mercury, Land Rover, Jaguar, Volvo, Aston Martin and Mazda -- are covered by the agreement.

"Subscriptions to Sirius have increased dramatically over the past several years," said Phil Martens, Ford's Group VP of product creation. "So, it's only natural that Ford would want to continue to make Sirius’ unique mix of programming available to Ford buyers in the future. Our relationship provides customers with the best of both worlds: innovative technology, style and driving experience."

Added Sirius CEO Mel Karmazin, “Ford buyers can be assured that our two companies will continue to work together in the future to make their driving experience even more pleasurable."

Land Rover recently announced plans to offer SIRIUS as a factory-installed option on select vehicle lines, beginning with the 2006 model year. Volvo, Jaguar and Mazda currently offer Sirius as a dealer-installed option, with future plans to offer Sirius as a factory-installed option and/or as an option installed as overseas vehicles enter U.S. ports.