Euro zone business activity slumps to 16-month low

Business activity in the euro zone fell to a 16-month low in November, according to data released on Wednesday, confirming fears that the region's economy is faltering.

Final euro zone composite Purchasing Manager's Index (PMI) data from Markit came in at 51.1 in November, below flash estimates of 51.4 released last month. It marks a fall from October's final reading of 52.1.

The composite reading measures both manufacturing and services activity, with the 50-point mark separating contraction from expansion.

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The figures could put more pressure on the European Central Bank (ECB) to increase stimulus measures ahead of its next monetary policy announcement on Thursday. There is growing pressure on the bank to start buying government bonds, although Germany has opposed the move to date.

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The euro zone data was preceded by disappointing services PMI figures for Germany and France, the euro zone's largest and second-largest economies respectively.

The slowdown across the 18-country region reflected weakness in new order inflows, as new business fell for the first time since July last year. Job creation also remained near-stagnant, Markit said.

Chris Williamson, chief economist at Markit, said there were "worrying signs" of economic performance deteriorating in the euro zone's core countries, which, if sustained, "could drive the region back into recession."

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"France remains the biggest concern, suffering an ongoing decline in business activity, but growth has also slowed to the weakest for one-and-a-half years in Germany," he added.

Heightened geopolitical tensions, particularly related to Russia and Ukraine, have weighed on confidence and investment across the euro zone, according to Howard Archer, chief European and U.K. economist at IHS, reinforcing the challenging conditions in many countries.

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"Credit conditions are currently still tight in many countries, unemployment remains elevated and seems likely to creep down at best over the coming months, private and public debt levels are high in a number of countries, while consumer purchasing power is constrained by generally limited wage growth," he said in a note Wednesday.

The weak November euro zone data are bad news for the ECB, Archer added, making it more likely that the ECB will eventually have to go down the quantitative easing (QE) route.

- By CNBC's Holly Ellyatt, follow her on Twitter @HollyEllyatt.