Sales of all vehicles in the US enjoyed a strong performance in July according to the latest figures released by the National Automobile Dealers Association (NADA).

Higher business spending, record levels of incentives and tax breaks all helped to drive sales of new cars and light trucks in July.

Delivering the highest monthly total of the year, July went some way to improving the year-to-date annualized rate.

'This relatively strong sales performance suggests that an improving stock market, the start of a renewal in corporate investment, and growing customer satisfaction are supporting sales of new vehicles,' said NADA chief economist Paul Taylor.

'The blistering 18.1 million unit annual pace for sales in July a year ago, as the Big Three renewed incentives, tends to mask the strength of last month's totals,' Taylor went on.

'But year-to-date sales are just 2.2 percent behind 2002, the fourth strongest year on record.'

Sectors that fared particularly well included utility vehicles, which soared 30 per cent, and luxury sport utility vehicles, which went up 20 per cent.

NADA represents more than 19,700 new car and truck dealers, with over 43,000 separate franchises.