US President Barack Obama is due to
unveil what he called "the biggest, most important step we have ever
taken" in tackling climate change.
US power stations are the country's largest source of greenhouse gases
The aim of the revised Clean Power Plan
is to cut greenhouse gas emissions from US power stations by nearly a
third within 15 years.
The measures will place significant emphasis on wind and solar power and other renewable energy sources.
However, opponents in the energy industry have vowed to fight the plan.
They say Mr Obama has declared "a war on
coal". Power plants fired by coal provide more than a third of the US
electricity supply.
The revised plan will aim to cut carbon emissions from the power sector by 32% by 2030, compared with 2005 levels.
Each US state will have an
emission-cutting goal assigned to it and must submit a proposal to the
Environmental Protection Agency on how it will meet the target.
The BBC's Tom Bateman in Washington says
President Obama will be hoping that Monday's announcement secures his
legacy on climate change.
The measures, our correspondent says,
would give the president the moral authority he needs to argue for
global reductions in greenhouse gases at a major conference in Paris
later this year.
However, several state governors are already saying they will simply ignore the plans.
In face of the criticism, the White
House said the release of the plan was "the starting gun for an all-out
climate push" by the president and his cabinet.
Hillary Clinton vow
In a video released by the White House,
Mr Obama said the new limits were backed up by decades of data showing
that without action the world faced more extreme weather and escalating
health problems.
"Climate change is not a problem for another generation. Not any more," Mr Obama said.
"My administration will release the
final version of America's Clean Power Plan, the biggest, most important
step we have ever taken to combat climate change."
Democratic presidential candidate Hillary Clinton said she would defend the plan if she was elected to replace Mr Obama.
"It will need defending. Because
Republican doubters and defeatists - including every Republican
candidate for president - won't offer any credible solution," she said.
"The truth is, they don't want one."
One Republican presidential candidate,
Marco Rubio, said the plan would be "catastrophic," while another,
former Florida governor Jeb Bush, said the plan was "irresponsible and
over-reaching".
Correspondents say the emphasis on
renewable energy sources marks a significant shift from the earlier
version of the plan that sought to speed up a transition from coal-fired
power to natural gas plants, which emit less carbon dioxide.
It is believed the revised plan will aim to keep the share of natural gas in US power generation at current levels.
Power stations are the largest source of greenhouse gases in the US and account for about one third of all such US emissions.
Source: BBC
