Reuters: About 175 nations agreed a plan on Sunday to revive climate talks after the Copenhagen summit but the U.N.’s top climate official predicted a full new treaty would be out of reach for 2010. Delegates at the three-day talks, which were held up for hours by bitter splits between rich and poor nations, agreed to hold two extra meetings, each at least a week long, in the second half of 2010 after the Copenhagen summit last December failed to reach a binding deal. The extra …