BRUSSELS — A top EU official warned Friday that the euro-area economy would shrink for the second year in a row and that such countries as France and Spain would miss fiscal targets meant to ensure the stability of the common currency.

Olli Rehn, the European commissioner for economic and monetary affairs, forecast growth across the 27-nation European Union of just 0.1 percent this year and a contraction of 0.3 percent among the 17 countries in the euro zone.