Brown upped the ante to an "entente formidable" after Sarkozy said that an "entente amicable" had replaced the "entente cordiale," The Telegraph reported.

"This is a new step in the dynamic relationship between Britain and France," Brown said at a joint news conference after a summit meeting of ministers from both countries. "Together we will tackle the challenges of a new global era."

Sarkozy hailed Brown for winning ratification of the new EU treaty without a referendum. The president urged Britain to become more closely involved in the European Union, pointing to its independence on its own currency, on border controls and on some criminal justice agreements.

The leaders acknowledged some potential disagreements in the near future. They include Sarkozy's desire to make the union a military force, which Britain fears would undermine NATO.