US:Stepping in where the Bush administration has refused to tread, California's governor, Arnold Schwarzenegger, and five other governors of western US states, joined by two Canadian provincial leaders, have pledged to enforce a tough regional cap on greenhouse gas emissions.
Under the Western Climate Initiative, the leaders agreed to slash emissions of carbon dioxide and other climate warming pollutants to 15 per cent below 2005 levels in their states and provinces - about the same percentage as California's commitment under last year's landmark global warming law.
Overall, the region would cut emissions by 350 million metric tonnes - the equivalent of more than 100 new coal-fired power stations.
To achieve their goal, the partners, including both Democratic and Republican governors, committed to designing a carbon trading system within a year. That approach, now in use in Europe, allows industries to trade pollution credits among themselves.
Seven northeastern and mid-Atlantic states are also designing a so-called "cap-and-trade" system, but that initiative will be limited to power stations.
"Climate change is a global problem that requires a global solution," Mr Schwarzenegger said in announcing the accord. "Our collective commitment will build a successful regional system to be linked with other efforts across the nation and eventually the world."
California officials took pointed aim at the Bush administration's refusal to enact a national programme to cut greenhouse gas emissions.
"The federal government needs to step up to the plate, but the states aren't waiting," said Linda Adams, California's secretary for environmental protection.
"Ideally, we would have a cap at the federal level," she added.
Although the Bush administration has rejected the Kyoto Protocol, a global climate pact, White House spokeswoman Dana Perino said that the charges of federal inaction are "false" and that Mr Bush is "supportive of actions by the states and respects the role governors play".
The administration, she said, had supported billions of dollars in incentives for clean-burning technology and building retrofitting, a legislative proposal to cut the nation's traditional gas use by 20 per cent over the next decade, as well as an effort to slow the growth of greenhouse emissions nationwide.
But in contrast to the administration's embrace of voluntary emissions targets, Mr Schwarzenegger has travelled the west in recent months, cajoling other political leaders to join in a commitment to fixed cuts.
Besides the states which have signed up - Arizona, New Mexico, Oregon, Washington, and Utah, along with British Columbia and Manitoba - several other states and provinces are official "observers", still considering whether to commit to the initiative's stringent goals.