Climate finance has emerged as the biggest stumbling block to progress at the high-stakes United Nations climate talks in Scotland in November. How the Group of 7 wealthy nations treats the issue Friday and Saturday may determine the outcome.

Why it matters: Providing the funding that was promised to developing countries might open up other areas of important conversation in Glasgow, such as setting more ambitious emissions reduction targets for 2030.

Flashback: In 2015, developed nations promised that beginning in 2020, they would provide $100 billion annually to developing nations to help them cope with the effects of climate change and transition their economies away from fossil fuels.

• This money has never fully materialized.

The big picture: Christiana Figueres, who chaired the Paris climate talks for the U.N. and is a founding partner of the NGO Global Optimism, told Bryan that the G7's credibility is on the line.

• "Without trust, especially between the global north and the global south, none of this is going to happen," Figueres said.
• Speaking of the $100 billion commitment, she said: "It is a political commitment and hence it has a very, very high symbolic value as really representing the trust that the global south can or cannot have in the global economy. That's why it's important."

Between the lines: "It's a very important totemic figure in terms of trusting the word of these leaders," said Saleemul Huq, who directs a climate and development NGO in Bangladesh, on a call with reporters.

• "To me, the issue is the credibility of the world's leaders, the seven biggest countries who have made these promises, or whether we believe anything they say at all."

The bottom line: "This is beginning to look like diplomatic ineptitude amongst the rich countries, because $100 billion really in the scale of things is not an extraordinary amount of money, and it is not beyond our capability to meet that promise, keep it, and then extend it," said Rachel Kyte, dean of the Fletcher School at Tufts University.

What we're watching: All eyes will be on the G7 leaders' communique to spot any progress on this issue, including any specific new monetary commitments from countries.

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