A closely watched survey is showing that economic growth across the 19-country eurozone is running at a six-year high.

Financial information company IHS Markit says its purchasing managers index — a broad gauge of business activity — rose to 56.7 points in April from 56.4 the previous month. That's the highest level since April 2011.

Anything above 50 indicates expansion, with the latest reading pointing to quarterly economic growth of 0.7 percent, which would be above the region's long-run average.

According to Chris Williamson, the firm's chief business economist, such strong growth, if sustained, will "inevitably lead to upward revisions to economists' 2017 forecasts."

He says the "robust" growth is being seen in both manufacturing and services, with the former "clearly benefiting" from the weak euro, which has boosted exports.