Volkswagen AG sees the newest Jetta model bolstering U.S. sales of the car by as much as 25 percent by 2012, helping the automaker seize up to 4 percent of the U.S. auto market.

Higher sales could boost the company's share to between 3.5 percent and 4 percent in the next two to three years, said Stefan Jacoby, Chief Executive of Volkswagen Group of America, Inc.

Improved U.S. consumer demand for cars and new models unveiled over the next two years will help the company reach that target.

So far in 2010, the automaker has 3.1 percent of the U.S. market. Jacoby said the latest model of the Jetta, the bread and butter of the company's U.S. sales, is a more attractive option for the American motorist.

It's a stylish car, Jacoby told Reuters on the sidelines of a Volkswagen event in New York on Tuesday. I'm convinced the American consumer loves that.

In the first five months of the year, the company's U.S. auto sales have risen 35 percent and executives expressed cautious optimism for the coming year.

But Jacoby said that June sales were feeling some impact from concerns over Greece's fiscal health and the euro's slide against the dollar.

In June, I think the impact of the Greece crisis and the euro crisis is somewhat visible, he told Reuters. Maybe this month is not so strong.

While sales are unlikely to be negative compared with year-ago levels, they have lost a little bit of momentum, Jacoby said.

Jetta sales typically average 100,000 a year. Jacoby expects the sales of the car to be between 120,000 to 130,000 vehicles in the next two years.

The latest model of the car, which was built in Puebla, Mexico, starts at about $16,000.

Overall the company's U.S. sales are expected to double as well to between 400,000 cars and 450,000 cars, boosted by a new generation of the Volkswagen Beetle vehicle and other new models, Jacoby said.

(Reporting by Deepa Seetharaman; editing by Gunna Dickson)