Buick has promised to introduce two new sedans in the next 12-18 months, and one of the two is a compact sedan based on the new Opel Astra.

Now, this new car leaks out spyshots in China, though a few weeks ago we had a chance to see the new car at the GM design studios in Warren, Michigan.

This 2010 Buick compact sedan, won’t look anything like the current almost unsellable Astra available from Saturn and will likely only be sold in North America as a four-door sedan.

So far, the Astra itself has only been shown as a five-door hatch although that may change when it is publicly displayed at the Frankfurt Motor Show later this month.

At this time, there is no word on what powertrains will go into the North American Buick, but four cylinder engines displacing between 1.6 and 2.0 liters are likely.

The 1.4-liter turbo that will go into the Cruze is also a possibility.

GM has said that a C-segment car like this could be built at its Lake Orion, MI assembly plant alongside the new Aveo, though it could also be built in Detroit with the Volt or in Lordstown, Ohio with the Cruze.

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