US President Barack Obama and Indian Prime Minister Manmohan Singh have agreed to step up co-operation on renewable energy sources and have signed an agreement pledging to speed up development and utilisation of clean energy sources.

Both countries hope the accord will help boost chances of an agreement at next month's Copenhagen Climate Summit. The United States and India are among the top five carbon dioxide emitters in the world.
 

The renewable energy pact, along with a raft of other agreements, was signed in Washington on the second day of Prime Minister Singh's week-long visit to the US. It is the Obama administration's first state visit and at a gala banquet on Tuesday evening, the president hailed India as an inspiration and as indispensable to democracy worldwide.