Countries blocking progress at crunch UN climate talks: hosts Spain

Some rich and developing countries are barring progress in vital United Nations climate talks, the COP 25 host Spain said Thursday.

Nations gathered in Madrid are struggling to finalise the rulebook of the 2015 landmark Paris climate accord, which aims to limit global temperature rises to "well below" two degrees Celsius and to a safer cap of 1.5C if possible.

"There are two very clear visions," Spain's minister for energy and climate change Teresa Ribera told reporters on the penultimate day of the two-week negotiations.

"There are those that want to move quicker and those that want to hide behind things which aren't working, so as not to advance things." The consensus-based talks are bogged down in politically charged wrangling over the architecture of carbon markets, timetables for the review of carbon-cutting pledges and a new fund to help poor countries already reeling from climate impacts.

Ribera said that some wealthier nations were slowing progress as their governments "weren't convinced of the need to act on the climate." "Because of this they are resisting moving forward," Ribera said.

The United States, history's biggest emitter, has said under President Donald Trump it is leaving the Paris agreement next year.

It has been accused of blocking progress on a number of issues in Madrid. Ribera did not name the US but referred to "even those who have said they are leaving Paris".

She said however that it was not just the wealthy emitters preventing things moving ahead.

"Other medium-sized economies are particularly cautious as they are making decisions that aren't compatible with (preventing) climate change," she said.

Ribera highlights those countries' investment in coal -- a highly polluting fuel scientists say makes the Paris goals impossible to achieve at current usage rates.

Countries are supposed to demonstrate renewed ambition for climate action during the Madrid talks, and have a deadline next year by which they must submit new action plans.

But observers and delegates say progress has been glacial, with countries still worlds' apart on a variety of issues.

Talks are meant to wrap up Friday, but COPs regularly run into the second weekend.