The euro zone has returned to recession, according to a prestigious survey closely watched by central bankers and economists.

Output in the currency union has fallen for the second straight month, according to the March Purchasing Managers' Index (PMI) published by Markit Economics — and the decline has accelerated.

The news will reawaken the debate about whether the European Central Bank and euro zone politicians are doing enough to save the economy from a serious slump.

Chris Williamson, chief economist at Markit, said, “The further drop in the PMI is clearly a disappointment following the brief return to growth seen in January and suggests that policymakers will need to seek ways to revive economic growth across the region again.”

The March PMI numbers painted a less sunny picture than before for Germany and France, which largely caused the deterioration in the euro zone as a whole. In particular, the powerful German manufacturing sector has put in a disappointing performance. Output showed anemic growth this month after a strong showing in February.

The composite index of output for the euro zone as a whole, including both manufacturing and private-sector services, fell to 48.7 from 49.3. Any figure below 50 means a contraction in output.