BERLIN -- Europe's largest automaker Volkswagen AG is reporting a 13.7 per cent increase in June passenger vehicle sales, with booming results outside western Europe where the debt crisis slowed spending.

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

Half year sales were up 10.2 per cent to 2.79 million vehicles delivered.

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

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

Volkswagen is warning of "considerable uncertainty" in Europe ahead in the second half.