Negotiations for a climate rescue pact got back on track Tuesday after an acrimonious start, as France's top diplomat urged "progress" ahead of a year-end conference to seal the deal.

"This week is critical," Foreign Minister Laurent Fabius told senior negotiators at the five-day huddle tasked with crafting a new blueprint for the UN summit in Paris.

"We are expecting from you... a new text," he said.

"Your leaders and the world are expecting this process to deliver a good text in Paris that address the challenges ahead of us."

The Bonn meeting must forge a workable blueprint for an agreement to be inked in Paris to crown more than two decades of fraught, 195-nation climate negotiations.

These are the final preparatory steps before world leaders open the November 30-December 11 UN conference.

The accord expected from it would be the first committing all the world's nations to climate action.

The talks opened on a sour note Monday when developing countries accused rich ones of "apartheid" tactics, and claimed their core demands had been excised from the blueprint.

After an over-night sprint to reintroduce omitted passages, the G77 bloc of developing nations -- home to the vast majority of the global population -- said Tuesday their key concerns had been addressed.

The revised draft, expanded from 20 pages to 34, managed to "correct imbalances", South African climate envoy Nozipho Mxakato-Diseko said on the group's behalf, paving the way for the technical negotiations to resume.

"We need to make progress in Bonn to succeed in Paris," Fabius insisted on a whistle-stop visit to the former West German capital.

- 'Our only home' -

The Bonn text will serve as a working document for ministers and heads of state who need to take the tough political decisions needed for the Paris summit to succeed.

The overarching goal is to limit global warming to two degrees Celsius (3.6 degrees Fahrenheit) over pre-Industrial Revolution levels.

Diplomats will have to make up for the first nearly day-and-a-half which should have been spent on line-by-line text bartering.

But all was not lost. At least "people really started listening to each other," said Cuba's chief negotiator Pedro Luis Pedrosa.

"Every delegation is very much aware that now we don't have more time. Either we get it right, or we don't get" an deal, he told AFP.

"Vulnerable countries need an agreement even more than the others, but we cannot just sign any old thing," added African group spokesman Seyni Nafo. "Now, we can talk."

Alix Mazounie of the NGO Climate Action Network said Monday's "crisis" helped refocus parties' attention "on what this agreement must deliver to those most in need, especially on financial issues."

A key pillar of the pact will be a list of national pledges to cut greenhouse gas emissions.

But poor nations demand funding to finance their transition to less carbon-polluting energy, and for shoring up defences against climate change-induced sea-level rise and storms.

Scientists say pledges submitted by more than 150 nations so far add up to warming closer to 3 C -- a world of dangerous sea-level rise, superstorms, drought and disease spread.

More than 150 religious leaders from around the world urged climate negotiators Tuesday to bequeath a liveable planet to future generations -- echoing recent appeals by Pope Francis and Islamic scholars.

And UN chief Ban Ki-moon, who on Monday described the talks as "slow" and "frustrating", called Tuesday on Canada's newly-elected Liberal leadership to play a strong role in advancing the talks.

The country's emissions target under conservative Stephen Harper were widely regarded as inadequate.

In Tibet, the Dalai Lama urged the world to protect his country from global warming.

"This blue planet is our only home and Tibet is its roof. As vital as the Arctic and Antarctic, it is the Third Pole," he said in a statement.