The gap between imports and exports of goods was at its widest for almost a year in September, according to the Office for National Statistics (ONS).
The ONS said the goods trade deficit widened to £9.816bn, compared with £9.557bn in August.
Including services, in which the UK traditionally has a surplus, the overall trade deficit also widened slightly to £3.268bn.
Separate ONS data brought disappointing news from the construction sector.
The ONS said the UK’s construction sector grew by 1.7% in the third quarter of 2013, but this was slower than the initial estimate of 2.5%.