The European Union must hand back half of its powers, former French President Nicolas Sarkozy said Saturday, stepping up his criticism of the 28-nation bloc as he seeks to be elected head of France's conservative party this week.

Just a few weeks after he called for the suspension of France's participation in Europe's borderless Schengen region, Sarkozy pressed on with increasingly Euroskeptic proposals rare among the country's mainstream politicians.

"I want us to eliminate half of Europe's current powers," Sarkozy said, adding that less than a dozen key policies including industrial policy, agriculture and research should remain. "Everything else must be given back to member states."