MELBOURNE, Nov 11 (Reuters Breakingviews) - The United States and China have given a bit of a lift to the United Nations COP26 gathering in Glasgow. The world’s two largest polluters issued a surprise joint statement on Wednesday pledging their resolve to “strengthen and accelerate climate action and cooperation”. It offers very little of what’s most important, namely a commitment to halve greenhouse-gas emissions by 2030 to restrict global warming to 1.5 degrees Celsius above pre-industrial levels, but nevertheless provides something of a psychological boost. There have been some notable misses at the United Nations-organised summit. China and the United States, for example, refused to sign an agreement to end sales of new petrol-powered vehicles read more by 2040. China, along with other big coal-dependent countries like India and Australia, also did not provide any written assurance to phase out the fossil fuel over the next two decades or so. As of Tuesday, actions unveiled so far leave the planet on track to warm by 2.4 degrees Celsius, according to the latest calculation from Climate Action Tracker.On the face of it, the U.S.-China communiqué does almost nothing to change the trajectory; the only real substantive addition is a welcome agreement by China to do more to reduce methane emissions. Politically, however, their statement is more powerful. For starters, simply having the two countries unite on a message is a victory of sorts. Since their joint proclamation in April, tensions between them have worsened, not least thanks to the so-called AUKUS pact in September for the United States and United Kingdom to sell nuclear submarines to Australia. Reinforcing the ambition shows they’re trying to separate climate change from more traditional diplomatic problems.It also should bolster their ability to exert suasion, especially on recalcitrant fossil-fuel states like Australia and Saudi Arabia. Those places may now find it harder to change what for the UN is some pretty forceful language in the COP26 draft agreement, like phasing out coal and subsidies for fossil fuels. Another section calls on members to improve their 2030 emissions-reduction targets within 12 months. What it lacks in detail, the eleventh-hour U.S.-China effort could make up for by helping everyone else set their sights higher. Follow @AntonyMCurrie and @gfhay on Twitter China and the United States on Nov. 10 issued a joint statement on enhancing action to combat climate change over the next decade. - The two countries said they intend to cooperate on issues from regulatory frameworks and environmental standards to policies to decarbonise and deploy technology such as carbon capture and storage. China also said it would develop a plan to reduce methane emissions.