The chief executive officer of Royal Dutch Shell PLC berated Washington yesterday for spurning the United Nations Kyoto agreement on global warming, saying U.S. backing for a global regulatory framework would create incentives for oil companies to reduce carbon dioxide emissions.

"For us as a company, the debate about CO2 is over. We've entered a debate about what we can do about it," Jeroen van der Veer told a gathering in Dubai of hundreds of political and business leaders from the Middle East and elsewhere.