Range Rover’s new 4.4-litre V8 diesel will not be sold in the US, according to company insiders.

The new unit, originally co-designed with Ford and built in Mexico, offers a significant improvement in economy and CO2 emissions over the old 3.6-litre V8 unit, but it’s still not enough to meet strict US emission laws.

Read Autocar's first drive of the Range Rover TDV8 2011

The current US emission laws are equivalent to Euro6 standards, which don’t come into force in Europe until 2014. The 4.4 V8 is engineered to meet Euro5 standards.

However, the next-generation version of the TDV8 engine is set to be launched in 2014/15, and Range Rover insiders said the engine is “very likely to come to the US then”.

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