Hopes that a big diesel will appear under the bonnet of a production Bentley are likely to be dashed, according to company bosses.

Chairman and CEO Franz-Josef Paefgen admitted some time ago that Bentley had experimented with diesels and found them impressive, but adverse market conditions make the move unlikely, the company now says.

See the official pics of the new Bentley Continental GT

“The forthcoming Euro 6 clean-air regs are likely to pile some big costs on to diesels,” says Bentley powertrain boss Brian Gush.

“And there’s a strong prejudice against them in the US and Japan, which are key markets for us. The attitude of Chinese buyers is going to have a big effect on cars like ours in future, too, and they are none too keen.

“Those of us who know diesels can see the benefits, but in large parts of the world the cars just wouldn’t sell."

Read the full story on the new Bentley Continental GT, plus see more pics

The new for 2011 Bentley Continental GT will have a choice of either Bentley’s familiar twin-turbo 6.0-litre W12 with a few minor tweaks or an all-new V8.

The 6.0-litre W12 will have changes made to its engine management electronics and some new low-friction measures that together boost both power and torque, from 552bhp to 567bhp and from 479lb ft to 516lb ft.Bentley isn’t saying much about its all-new V8 except that the capacity is 4.0 litres.

It is highly likely to be turbocharged and it’ll come a year after the new Conti’s launch next March. The V8 version will still have four-wheel drive, engineers say.

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