The eurozone's economy unexpectedly stalled in the second quarter of the year, dragged down by shrinking growth in Germany and stagnant France, ringing alarm bells about the health of the bloc's economy as it braces for impact of sanctions against Russia.

The 18 countries in the eurozone showed no growth in the three months to June when compared with the first quarter, when growth was 0.2 percent, data from the EU's statistics office Eurostat showed on Thursday.

The worse-than-expected performance of one of the world's biggest economies is a warning ahead of the incoming quarter, when the European Union will feel hard impacts of sanctions against Russia imposed in July over its involvement in Ukraine crisis.