Chirac has demanded that the United States sign both the Kyoto climate protocol and a future agreement that will take effect when the Kyoto accord runs out in 2012, according to an article in the New York Times.

If the U.S. does not sign the agreements, he said, a carbon tax across Europe could apply to imports from nations that have not signed the Kyoto treaty.The European Union being the largest export market for American goods, such a tax could encourage compliance.

Chirac previously mentioned the possibility of a carbon tax, in his 2007 New Year's speech. At that time he called for an international conference to be held in Paris at the beginning of this month to increase awareness.

In November 2006 French Prime Minister Dominique de Villepin said countries that do not commit to new targets to cut greenhouse gas emissions should not be allowed to benefit by avoiding the costs associated with reducing global warming.

Chirac noted that many American politicians now favor emissions cuts, and mentioned President Bush's State of the Union address in which Bush described climate change as a “serious challenge.”

Politically speaking, environmentalism has not been Bush's strong suit, and it hasn't been Chirac's, either. As Europe negotiates agreements on farm practices and subsidies, Chirac has been criticized for supporting environmentally unfriendly agricultural methods. Bush has held up France as an example of a nuclear energy success story, while Chirac's government has come under increasing scrutiny for its handling of radioactive waste.