BRUSSELS Euro zone economic growth was weaker than expected in the third quarter, a flash estimate showed on Tuesday, with gross domestic product contracting slightly quarter-on-quarter and the year-on-year growth rate slowing sharply.

The European Union's statistics office Eurostat said GDP in the 20 countries sharing the euro fell 0.1% quarter-on-quarter in the July-September period for a 0.1% year-on-year rise.

Economists polled by Reuters had expected a 0.0% quarterly growth and a 0.2% year-on-year gain.

Eurostat data showed 0.1% quarterly growth in France, 0.3% in Spain and 0.5% in Belgium, but that failed to offset a 0.1% quarterly slump in Germany, no growth in Italy, and contractions in Austria, Portugal, Ireland, Estonia and Lithuania.

The euro zone economy is facing strong headwinds from high inflation and record high interest rates and slowly tightening fiscal policy.

(Reporting by Jan Strupczewski)