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The EU has become the most powerful trading bloc in the world with a GDP nearly as large as that of the United States.
The creation of the euro as a single currency for 12 EU members has led to ever closer economic links, but currently its biggest economy, Germany, has gone into recession.
The EU is also facing the prospect of integrating the 10 new members from the poorer regions of Eastern Europe, who joined in May 2004, into its economic system.
The EU has found it difficult to shed its protectionist past based on the idea of self-sufficiency in agriculture which limits agricultural exports from the other countries, but will implement a major reform of its Common Agricultural Policy in January 2005.