Speculation is increasing that US car giant General Motors could cut third quarter production when it officially reports new sales figures for June tomorrow.

Analysts say the figures have been affected by May sales which rose to their highest level in nine months because of industry attempts to massage the market with discounts and other promotions.

Paul Ballew, GM's head of sales analysis, admitted the June figures were weaker than predicted and helped intensify speculation by saying the manufacturer needed "to come down about 100,000 units between now and the end of the year."

Industry sales overall during the year ended May 31 hit 17.8 million. In June light vehicle sales fell year on year from 16.5m to 16.3m.

Data sourced from: USA Today; additional content by WARC staff