The French economy grew stronger-than-expected 0.6 percent in the first quarter after growing 0.4 percent the previous three months, the INSEE national statistics agency said on Monday.

A poll of 15 analysts surveyed by Reuters had forecast growth for the euro zone's second-largest economy to remain at the 0.5 percent INSEE had initially reported in its preliminary estimate.

Growth in the quarter to end-March was driven by a 1.0 percent surge in consumer spending and a 1.6 percent increase in investment, INSEE said.