Step Vaessen, Al Jazeera's correspondent in Bali, reported: "Some delegates had given up on this road map and started to pack up, but an agreement came at the very, very last minute.
"A lot of negotiations are still to be made. There are no emissions targets in this road map, but for developing countries it looks a lot better after this US concession… they want rich nations to take the lead on climate change."
The agreement between the 190 member countries of the UN Framework Convention on Climate Change (UNFCCC) came after an extension to 13 days of talks.
European and US delegates had sparred over the European Union's proposal that the Bali mandate set a 25 to 40 per cent cut in industrial nations' emissions by 2020, compared to 1990.
Those numbers were omitted from the text of the final agreement, with only an indirect reference present.
Ban Ki-moon, centre, appealed to delegates
to reach a consensus [AFP]
The negotiations had also stalled over appeals by developing nations that their need for technological help from developed countries receive more recognition.
A compromise deal had looked increasingly unlikely before the US decision, prompting Ban Ki-moon, UN secretary-general, to call for delegates to work together.
"Your work is not yet over ... everybody should be able to make compromises. You have in your hands the ability to deliver to the peoples of the world a successful outcome," he said.
Amid concerns that no deal would be reached on a road map for negotiations, Yvo de Boer, executive secretary of the UNFCCCC, broke down in frustration.
The agreement is a step towards talks aimed at slowing climate change, which the UN climate panel says is caused by human activity.
Rising global temperatures could cause a significant rise in sea levels and storms and intensify droughts, prompting mass migration of climate refugees.
After the road map was agreed, talks towards a new treaty to succeed the Kyoto protocol are scheduled to take place in Copenhagen, Denmark, in 2009.
Kyoto binds all industrial countries, except the US which has not signed up to it, to cut emissions of greenhouse gases between 2008 and 2012.
The new negotiations will seek to bind all countries, including developing nations, to limits in emission from 2013.