Connecticut Sen. Joseph Lieberman, a potential 2004 Democratic presidential candidate, joined Al Gore and others on Earth Day in criticizing President Bush’s environmental policies.

“There has not been a significant pro-environment initiative that’s come out of this administration,” Lieberman said Monday in some of his sharpest criticism of Bush since he and Gore, the 2000 Democratic vice presidential and presidential candidates, respectively, lost the election.

“I don’t think they’re reflecting the mainstream values of the American people, which really are pro-environment, across party lines,” Lieberman said in a conference call with reporters.

Meanwhile, Bush delivered an environmental speech in New York’s Adirondack Mountains. He said the 1990 Clean Air Act, stemming from his father’s tenure, was a good start and, “Now we should do more.”

Bush has asked Congress to impose mandatory limits on industry production of three kinds of pollutants and to let companies work out how to achieve them through a system of earning and trading credits. The pollutants are acid-rain-causing sulfur dioxide, smog-causing nitrogen oxide and mercury, a toxic chemical that contaminates waterways and goes up the food chain through fish to people.

His “clear skies” plan, which Congress has yet to consider, can “significantly reduce smog and mercury emissions as well as stop acid rain,” Bush said.

But critics said the plan would ultimately allow more emissions than permitted under current law.

Lieberman argued that the plan would result in at least double the levels of acid rain-causing pollution as a competing plan he has introduced with Sens. Susan Collins, R-Maine, and Jim Jeffords, I-Vt.

“The clear skies proposal is affirmative, but it’s inadequate,” said Lieberman. “It’s not as good … as existing law if properly enforced. That’s not much progress.”

Lieberman has said he won’t seek the 2004 nomination if Gore does. On Monday, he welcomed Gore, who wrote the environmental book “Earth in the Balance” in 1992, into the policy fray.

“The country benefits from having Al Gore’s voice back in national debates, and particularly on the environment,” Lieberman said. He said Bush was making a “series of steps backward yielding to polluters. The more of us who are speaking out on it, the better the country’s going to be.”

–Associated Press