WASHINGTON - Burning midnight oil, dozens of senators seeking to push climate change higher up the US political agenda launched into a rare all-night session Monday highlighting the need to reduce the global warming threat.
At least 28 Democrats including Senate Majority Leader Harry Reid were participating in the session - mocked by Republicans as a stunt - that began after the last vote Monday and was due to wrap up Tuesday morning.
The overnighter is the first major effort by the newly-created Climate Action Task Force in Congress, which wants to kick-start public debate on climate change.
The coterie of Democrats was "sending a clear message: it's time for Congress to wake up and get serious about addressing this issue," Senator Sheldon Whitehouse said.
The effort is backed by President Barack Obama, who has signalled he will use his executive authority wherever possible to reduce greenhouse gas emissions.
Obama "has taken steps in his first term and again in his second term and will continue to take steps to... reduce our carbon emissions," White House spokesman Jay Carney told reporters.
Climate legislation is opposed by many Republicans - and some Democrats - and faces tough opposition in Congress.
The issue is especially touchy this year, as lawmakers kick off campaigning for the November midterm elections, and legislation on the issue is unlikely to pass a divided Congress in 2014.