The European Central Bank cut a key interest rate by half a percentage point from 2.5 percent to 2 percent on Thursday as concerns about the economy in the euro zone rose on dismal economic data.

The key rate hadn't been 2 percent since December 2005.

When the ECB cut interest rates to 2.5 percent in December, its president Jean-Claude Trichet said the cuts and the government rescue plans should be allowed to work through, the Financial Times reported.