Brussels, Belgium ? European Union environment ministers agreed Tuesday on an ambitious target to cut greenhouse gas emissions by 2020 in one of the boldest moves yet to contain global warming – a goal likely to lead to mandatory limits for cars and pollution allowances for airlines.

But the goal – to cut emissions to 20 percent below their 1990 levels – could put a heavy burden on the EU’s newest members, and it was unclear how much of the load wealthier nations would shoulder.

The ministers said the target could be pushed up to 30 percent below the 1990 levels if other industrial countries sign on to a global effort.

German Environment Minister Sigmar Gabriel said many European colleagues had spoken of a moral duty toward future generations during the talks.

“Those who took the floor said that their daughters asked them exactly what they did when they came to such meetings and did they come home with good results,” he said. “I think that’s a pretty good incentive.”

The target, which must be approved at an EU summit next month, is a critical first step in a global warming strategy that must be in place by the time the Kyoto Protocol expires in 2012. The protocol requires 35 industrial nations to cut carbon dioxide and other harmful gases collectively by 5 percent from 1990 levels.

The EU ministers called for U.N.-led talks to finish by 2009 to fix a new climate change goal after Kyoto expires. The next agreement should include the United States – which rejected Kyoto – and other less-developed polluting countries like India, China, Mexico, Brazil and South Africa.

President Bush has kept the United States – by far the biggest emitter of carbon dioxide and other gases blamed by scientists for global warming – out of the Kyoto treaty, saying it would harm the U.S. economy.

The Bush administration has said it is committed instead to advancing and investing in new technologies to combat global warming. It has set a goal of reducing “greenhouse gas intensity,” which measures the ratio of greenhouse gas emissions to economic output, by 18 percent by 2012.

A U.N. climate official praised the new European target as “a milestone” in efforts to bring down emissions from industrial countries by 60 percent to 80 percent by mid-century, which scientists say is necessary to curb the Earth’s potentially disastrous rising temperatures.