Pope Francis is no longer planning to attend the critical United Nations climate summit that begins in three weeks in Glasgow, Scotland, the Vatican announced Friday.

Why it matters: Francis' attendance, given his global stature, could have helped provide momentum to what are expected to be difficult talks aimed at spurring more aggressive steps to cut greenhouse gas emissions.

• Emissions and finance pledges under the Paris climate agreement are non-binding and at each nation's discretion, so diplomacy and persuasion are important to securing stronger action.

Driving the news: The Vatican's delegation will be lead by Cardinal Pietro Parolin, the secretary of state, according to Matteo Bruni, director of the Vatican Press Office.

• No explanation was given, per the Associated Press, but Francis, 84, had intestinal surgery in July.

What we're watching: The rest of the RSVP list for the heads of state portion that occurs early in the two-week summit that starts Oct. 31.

• President Biden is slated to attend along with many other leaders, but plans by heads of some key nations remain unclear.
• In particular, officials in China — the world's largest greenhouse gas emitter — have not said whether President Xi Jinping will go.

The big picture: The summit, known as COP26, comes as global emissions are nowhere close to beginning the steep downward path needed to meet the goals of the 2015 Paris climate agreement.

• The agreement calls for limiting warming to "well below" 2°C compared to preindustrial levels, and ideally limit temperature rise to 1.5°C.
• Those are benchmarks for avoiding some of the worst harms and risks from climate change beyond the damaging effects already taking hold and sure to worsen.