New Delhi, Oct. 8 -- US luxury spending fell for a third consecutive month in September, pointing to growing caution among American shoppers even as luxury brands continue to rely on the country's wealthy consumers to offset weakness in other major markets.

Overall US luxury credit card purchases declined 6% year-on-year in September, following 4% declines in both July and August, according to Citi. The data is based on millions of credit card transactions.

The slowdown comes as the US heads towards the November 3 midterm elections, with surveys from the Conference Board and the University of Michigan showing growing unease about the US economy.

Buffeted by prolonged weakness in China and the economic fallout of the Iran war, luxury br...