The US-brokered deal with India and three other emerging economies went down to the wire with a personal push by President Barack Obama, even as developing nations appeared to have staved off attempts to subject their voluntary mitigation actions to international review.
The 12-day climate talks spilled overnight with consensus eluding on a substantive agreement and world leaders delayed their departures to meet again to find common ground amid serious attempts by rich nations to break the ranks of the developing countries.
The leaders of the group of four -- India, China, South Africa, and Brazil (BASIC) -- met again as the deadlock continued.
"The concerns of the developing countries was the verification of their nationally accountable mitigation actions," an official privy to the talks said.
The developing countries felt that any international review of their voluntary mitigation actions would mean an intrusion on their sovereignty.
Several drafts went back and forth as Obama waited for the BASIC leaders to conclude their discussions. The rich nations were also pressing for a 50 per cent emission cut across the board, which the developing nations were not ready to accept.