A poor performance by Singapore's exporters in the third quarter of this year has dragged down the full-year forecast for export growth.

Non-oil domestic exports slipped 3.3 per cent in the July to September period over a year ago, trade agency IE Singapore said on Thursday. Exports have now shrunk 7.1 per cent in the first nine months of the year.

Given this, IE Singapore expects exports to contract between 4 and 5 per cent for this year.

It is tipping a better performance next year, with export growth of 1 to 3 per cent, the agency said.

Despite the lacklustre showing by exports, Singapore's total trade rebounded in the third quarter to grow 6 per cent over the same period last year.

Non-oil re-exports jumped 11.7 per cent in the quarter, the second consecutive quarter of double-digit growth, said IE Singapore.

Total trade is forecast to grow 1 to 2 per cent for both this year and next year.