WASHINGTON?In their sharpest clash since the 2000 campaign, President Bush and Al Gore gave dueling Earth Day speeches Monday?Bush touting his plan to combat air pollution and his former rival contending the White House is sabotaging environmental protections.

Bush was spotlighting a market-based proposal on air pollution at Lake Everest, in New York state’s acid rain plagued mountains.

The president has asked Congress to approve mandatory limits on total industry output of sulfur dioxide, nitrogen oxide and mercury, letting companies work out how to achieve them through a system of earning credits.

Gore contends Bush’s plan would allow more toxic emissions than under current law.

“Put simply, on the environment, this administration has consistently sold out America’s future in return for short-term political gains,” Gore said in a New York Times guest column Sunday.