Euro zone sentiment turned positive for the first time in more than two years in September as investors welcomed the end of the bloc's recession and became increasingly upbeat about their current situation and outlook, a survey showed on Monday.

Sentix research group said its index tracking investor sentiment in the euro zone swung to +6.5 points, its highest level since May 2011, from -4.9 points in August.

The reading, which beat a Reuters poll for a rise to -2.8, was the first one in positive territory since July 2011.

"This is the second strongest rise of the indicator since its start in 2003," Sentix analyst Sebastian Wanke said in a statement. "It's a stunning coup for the euro zone."

Sentix said the 893 investors it surveyed between September 5 and 7 were largely more upbeat about their current business situation as well as about their six-month outlook.

Its sub-index on the current situation rose to -8.8 points, its highest since October 2011, from -22.3 in August, while a reading on expectations increased to 23.0 points from 14.3.

A bounce in exports and spending pulled the euro zone out of recession in the second quarter of 2013, the first signs of recovery after the bloc's longest slump.

The index on Germany, Europe's largest economy, climbed to its highest level since April 2011, reaching 28.4 points in September after 20.3 in August.