President Barack Obama on Saturday said the US has reached a "meaningful" deal to curb greenhouse gas emissions with four emerging economies, including India, but warned it was not enough to battle climate change.
"It is going to be very hard, and it's going to take some time (to achieve a legally binding deal)," he said at the conclusion of the Copenhagen Climate Change Summit.
"We have come a long way, but we have much further to go."
The deal reached by the US, India, China, South Africa and Brazil includes a method for verifying reductions of heat-trapping gases, a senior Obama administration official said.
He said under the agreement, each country also will list the actions they will take to cut global warming pollution by specific amounts.
The deal reiterates a goal that G-8 countries set earlier this year on long-term emission cuts and provides a mechanism to help poor countries prepare for climate change.
The agreement between the US and BASIC countries was achieved after Obama held talks with leaders of the four countries, including Prime Minister Manmohan Singh.
Both Obama and Singh delayed their departure from the Danish capital as world leaders went into an extra night of discussions in a bid to hammer out a deal on climate change.
Obama was quoted as saying by foreign agencies that there is a "fundamental deadlock in perspectives" between big, industrially developed countries like the United States and poorer, though sometimes large, developing nations.
What Manmohan Singh should tell Barack Obama
What the Copenhagen climate summit is all about
India to invest Rs 74,000 cr in CO2 cutbacks
Image: Obama at the Great Wall of China
Obama to meet Dr Singh on April 2