Clinton boosts climate aid pledge at summit on the brink

But Clinton said at a news conference the pledge is contingent upon China agreeing to transparency measures that allow other nations to ensure the world's biggest emitter is following through on vows to curb greenhouse gases, according to Reuters and other news services.

Update: High-level officials at the talks are sounding quite pessimistic about the prospects for reaching a truly substantive agreement, according to the Washington Post, Reuters and other outlets. It's unclear if Clinton's pledge can help break the logjam.