The governor of the southern U.S. state of Florida has signed some of the nation's toughest laws aimed at reducing greenhouse gases. In Miami, VOA's Brian Wagner reports that environmentalists are urging Florida and other states to craft their own environmental policies because they say federal officials have been slow to act.

Florida Governor Charlie Crist signed the measures into law during an environmental conference with researchers, business leaders and environmental protection groups.

State officials organized the event to highlight environmental research being done at local universities, and to generate interest in more environmental-friendly business practices.

Crist has sought to take the lead on environmental issues by installing solar panels on the governor's mansion and driving a vehicle that can run on ethanol.

He says he hopes his state's actions will spur others to act to reduce their role in global warming, which many scientists believe is caused by greenhouse gas emissions.

"Scientists say that climate change could endanger Florida's agricultural industry, cause violent patterns, jeopardize also our water supply," he said. "These are things we must address, things we are addressing."

Under the new rules, Florida's power companies must reduce power plant emissions and increase the share of power from renewable energy sources from about two percent to 20 percent. The measures also will require automobile emissions to be lower than federal standards.

Environmental groups say Florida's pollution controls will be some of the toughest in the nation. They say they provide an example for other states.

Critics of the federal government say Washington has been too slow to raise environmental standards in recent years, prompting Florida and many other states to pass their own legislation. The U.S. Congress is expected to consider legislation to create stronger emission controls later this year.

Terry Tamminen, an environmentalist who advised Florida on the new measures and spoke at the conference, said action at the state level may help pressure the federal government.

"I think we are at a political tipping point," he said. "So your leadership, Governor Crist, on this issue is absolutely essential to winning the battle here in the United States, which in turn will send the message to China, India and many other countries around the world."

Earlier this year, President Bush called for a series of meetings with 15 key nations to agree on new global targets for reducing greenhouse gases. A recent Dutch report says China has surpassed the United States as the largest emitter of carbon dioxide, the gas blamed for global warming. U.S. officials have said any international plan must include China and India.