MADRID -- Canada's newly minted environment minister is among the leaders expressing disapointment at Sunday's lacklustre resolution of marathon UN climate talks in Madrid.

Jonathan Wilkinson joined the chorus of dispirited delegates following the two-week COP25 conference, saying he and his team weren't satisfied by the decision to postpone debate about rules for international carbon markets for another year.

"Canada came to #COP25 in the spirit of compromise and commitment to action," he tweeted. "While there were some successes, we are disappointed that the world was not able to agree on the rules for the international carbon markets that would help us all raise our ambition in Madrid."

The talks stretched well beyond the planned Friday end date, as major polluters resisted calls to ramp up efforts to keep global warming at bay.

In addition to postponing the carbon markets debate, negotiators endorsed a general call for greater efforts to tackle climate change and several measures to help poor countries respond and adapt to its impacts.

The final declaration cited an "urgent need" to cut planet-heating greenhouse gases in line with the goals of the landmark 2015 Paris climate change accord. But it fell far short of explicitly demanding that countries submit bolder emissions proposals next year, which developing countries and environmentalists had demanded.

The Paris accord established a common goal of keeping temperature increases below 2 degrees Celsius, ideally 1.5 degrees Celsius, by the end of the century. So far, the world is on course for a 3- to 4-degree Celsius rise, with potentially dramatic consequences for many countries, including rising sea levels and fiercer storms.

Wilkinson, who was sworn in late last month and received his mandate letter on Friday, wrote on Twitter that Canada would continue to work towards those targets, and noted that Canada had committed to achieving net-zero emissions by 2050.

After two nights of difficult negotiations, delegates in Madrid opted to defer some of the thorniest issues to the next UN climate summit in Glasgow in November.

Chile's Environment Minister Carolina Schmidt, who chaired the meeting, said she was "sad" no deal had been reached on the rules for international trading in carbon emissions permits.

"We were on the verge," she said, adding that the goal was to establish markets that are "robust and environmentally sustainable."

UN Secretary-General Antonio Guterres, too, said he was disappointed by the meeting's outcome.

"The international community lost an important opportunity to show increased ambition on mitigation, adaptation and finance to tackle the climate crisis," he said. "We must not give up and I will not give up."

This report by The Canadian Press was first published Dec. 15, 2019.

With files by The Associated Press.