The Range Rover and Range Rover Sport will soon get optional diesel-hybrid power in the U.S.

A senior Land Rover official has confirmed rumors that the brand will offer its new diesel-hybrid powertrain in the United States.

"It's not a matter of 'if,' but 'when,'" Andy Goss, the current CEO of Jaguar Land Rover USA and soon-to-be company marketing chief, told The Detroit Bureau.

Originally announced only for the European market, the hybrid system teams a 3.0-liter turbodiesel V6 with a 47-horsepower electric motor for a combined output of 355 horsepower and 516 lb-ft of torque.

With the help of an eight-speed automatic gearbox that sends power to all four wheels, the setup enables the hefty Range Rover to return 44 mpg combined in the EU's somewhat optimistic test cycle. Despite that efficiency - and the hybrid gear's 264 pounds of additional weight - the SUV is still capable of sprinting from zero-to-62 mph in 6.9 seconds.

Land Rover plans to offer the system on the Range Rover Sport in addition to the standard Range Rover.

It isn't yet clear what price premium the diesel-hybrids will carry over their conventionally-powered siblings, but given the extra thousands that typical diesel and hybrid powertrains command by themselves, a model with both could be an expensive proposition.

Also unknown is exactly when the hybridized Rangies will launch. Given the looming U.S. mileage regulations, Land Rover will likely have an incentive to bring the SUVs to showrooms sooner rather than later