Four-year global effort to craft a binding deal to brake rising world temperatures enters intense home stretch

Paris talks on global climate deal resume after one-day break

Biggest issues unresolved; a "week of compromise" ahead

U.S.'s Kerry and other ministers to debate finance, measurement

PARIS, Dec 7 (Reuters) - A four-year global effort to craft a binding deal to brake rising world temperatures enters an intense home stretch on Monday, with senior officials in Paris stepping up pressure to resolve the most contentious points.

U.S. Secretary of State John Kerry, dispatched to secure a deal meant to cement President Barack Obama's legacy as a guardian of the environment, arrives in Paris to work alongside ministers from almost 200 nations attempting to steer the world away from fossil fuels.

In approving a pared-down draft text on Saturday, negotiators handed over the toughest questions to their bosses, who will spend the next week hammering out thorny issues including a system for funding developing nations and the mechanisms for monitoring national pledges to reduce emissions.

After a one-day break in talks, U.N. Secretary-General Ban Ki-moon will address the summit on Monday, followed by two days of brief speeches from nearly every nation. They are due to reach a final accord on Friday, but the talks are widely expected to run into overtime, as previous summits have.

While officials have been pleased with progress halfway through the two-week summit, Indian Environment Minister Prakash Javadekar cautioned that "substance-wise, we are not midway but ... at a crossroads".

He reiterated New Delhi's demand that richer nations must shoulder the biggest curbs to "pay back their debt for the overdraft that they have drawn on the carbon space", highlighting one of the most difficult obstacles to a deal.

'AMBITION' AND 'DIFFERENTIATION'

To speed things along, the host, French Foreign Minister Laurent Fabius, has formed working committees headed by ministers to tackle the biggest themes, which include "differentiation" (the distinction between rich and poor nations, critical for questions of financing) and "ambition" (how to improve on national efforts in future).

Some form of agreement seems assured, with major powers eager to avoid the failure of the last summit in Copenhagen, six years ago.

It is expected to be the strongest global pact yet to bind both rich and developing nations to curbing the rise in the fossil fuel emissions responsible for climate change, even though officials say it will not be enough to prevent global temperatures rising past a dangerous threshold of 2 degrees Celsius (3.6 Fahrenheit) over pre-industrial times.

Just how strong the accord will be remains to be seen. Some nations want a commitment to phase out fossil fuels by the middle of the century; others see that as unrealistic. Some of the most vulnerable countries, such as low-lying islands, want firm language on how rich nations who have emitted the most will pay for the future damage caused by rising seas.

"Nobody has taken away anything they really want off the table yet," Jennifer Morgan, of the World Resources Institute think-tank, told Reuters. "Nothing has been solved."

As European Climate Commissioner Miguel Arias Canete said, this coming week will be "the week of compromise".

(Reporting by Alister Doyle, Barbara Lewis, Bate Felix, Emmanuel Jarry in Paris; Writing by Jonathan Leff; Editing by Kevin Liffey)

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