“Co-operation is the only choice for both China and the US,” Xie told reporters via a translator in Glasgow.
“By working together, our two countries can achieve many important things that are beneficial, not only to our two countries, but to the world as a whole. As two major powers in the world, China and the US shoulder special international responsibilities and obligations.”
By quarantining climate from their broader competition, it began to look as though China and the US had found not only an effective way to battle warming, but a valve to release tension between them as it grew over other issues.
Then in August, China, infuriated by House Speaker Nancy Pelosi, pulled the plug on climate talks.
Now both Kerry and Xie - and their teams of advisors - are in Sharm el-Sheikh, where they have not been able to hold official talks.
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Tension over the issue of Loss and Damage finance - which China backs and US opposes - has spilled over into other areas of negotiation, gumming up a process that demands the consensus of nearly 200 nations.
Now that their leaders have declared these two men, who have worked together on climate now for a decade, can once again officially engage, many hope the broader negotiations will improve.
“They are the centre of gravity,” says Li Shuo, senior policy advisor for Greenpeace China who is in Egypt for the talks, explains.
“When they talk, it helps calm down tension.
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“The climate agenda is a very special one in the bilateral relationship. It is different to economic or trade or political issues in that it is not just the interests of these two countries that are at stake, but [those of] the entire world.
“So that requires of them that they set aside their differences to work in the interests of the entire global community.”
Li says the relief in the negotiating rooms in Egypt on Monday was real, but warns against indulging in too much optimism.
“I would stress that all we are seeing here is that they have prevented the worst outcome, which would be some sort of climate policy decoupling.
“What we need to see from them is leadership.”
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