The euro zone's trade surplus narrowed less than expected year on year in March, data showed today.

This indicated that net trade was one of the main drivers of economic growth at the start of the year for the single currency bloc.

The external trade surplus of the 18 countries sharing the euro, unadjusted for seasonal swings, was €17.1 billion in March, down from €21.9 billion in the same time of last year, data from the EU's statistics office showed.

Analysts polled by Reuters had expected a €15.5 billion surplus compared with the originally reported surplus of €13.6 billion in February, which was revised up to €14.2 billion.

Non-seasonally adjusted exports fell 1% on the year in March. Month-on-month and adjusted for seasonal factors, exports fell 0.5%.

In the first three months of the year, euro zone exports grew 1% year-on-year to €465.6 billion.

The euro zone economy grew much less than expected at 0.2% in the first three months of the year, hit by economic malaise in France and Italy, which was partly compensated by a strong 0.8% rise in Germany. 

Germany is Europe's biggest exporter. Its trade surplus grew further in first two months of the year to €31.7 billion from €30.4 billion the same time last year. 

The UK remains the euro zone's biggest trade partner, with exports growing 10% on the year in January to February period and imports down by 5%.  

Exports into the second largest trade peer, the US, and third China were also up, while exports to fourth Russia fell by 13% on the year and imports dropped 9% in the first two months of the year.