Figures compiled by the British Chambers of Commerce (BCC) suggested that while the UK was still growing, expansion slowed during the period, with a poll of more than 7,000 firms showing the increase in domestic sales and orders in manufacturing dropped sharply following all-time highs in the second quarter.
Growth in exports fell for both manufacturing and the dominant services sector, which represents three-quarters of UK output.
BCC chief economist David Kern said: "These results point to continued UK economic growth, but the pace is easing. The signs of the slowdown are particularly noticeable in manufacturing, where all the key domestic and export balances recorded declines in Q3.
"Noticeable falls in all the export balances and increased signs of slower growth require a forceful policy response.
"UK growth cannot rely permanently on consumer spending, and on unsustainable current account and budget deficits. Unless...