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By Maria Martinez

July 9 (Reuters) - German exports rose unexpectedly in May, increasing by 0.9% compared with the previous month, data from the federal statistics office showed on Thursday.

The result compared with a forecast 0.3% decrease in a Reuters poll.

Imports were down 2.5% on a calendar and seasonally adjusted basis.

The foreign trade balance showed a surplus of €19.1 billion in May, up from €14.7 billion in April.

Exports to EU countries dropped by 1.1% on the month, while exports of goods to countries outside the EU increased by 3.6%.