"Bush's plans to increase drilling for fossil fuels and increase nuclear capacity are potentially disastrous," Lambert said at the launch of the Green's campaign for Britain's June 7 general election.

"He is taking the completely wrong direction and should be concerned with reducing demand for energy, not with producing more of it. We will certainly focus on Bush and his environmental policies at the summit in Sweden," Lambert said, referring to the Gothenburg meeting set for June 13.

While the Greens have yet to make headway in mainstream British politics, they are a political player in parts of continental Europe, and have become a potent force in Germany.

Bush, who has been slammed by international environmental groups over his plans to expand U.S. coal, oil and nuclear power production, is scheduled to attend the summit.

He has called his energy strategy a remedy to "the most serious energy shortage" since the 1970s.

But the European Commission unveiled its own strategy earlier this week to put environmental protection at the heart of all its policies and to make the EU the world leader in sustainable economic development.

Europe and the United States have locked horns over environmental policy since Bush pulled out of the 1997 Kyoto climate change deal in March.

European Commission President Romano Prodi will submit his paper, "A Sustainable Europe for a Better World", to EU Leaders at the summit.