Volkswagen, Europe's biggest car-maker, has reported a 13.7% increase in passenger vehicle sales in June, with booming results outside Western Europe where the debt crisis slowed spending.

The company, based in Wolfsburg, Germany, said today that June sales rose to 498,600 cars from 438,400 in June 2011.

Half-year sales were up 10.2% to 2.79 million vehicles delivered.

In the first six months, sales were up in North America by 24.2% to 295,300, 15% in the Asia-Pacific region to 1.09 million vehicles, and 45.2% in Eastern Europe to 134,000.

Western European sales, excluding Germany, for the half year slipped 4.7% to 464,300 vehicles, while German sales rose only 2.6% to 309,700.

Volkswagen has warned of "considerable uncertainty" in Europe in the second half.