* Obama detailed climate change agenda on Tuesday
* Pledged new rules to cut power plant emissions
* U.N.'s Figueres says effect of reforms must be measured
* Says countries on track for 2015 climate deal
By Daren Butler
ISTANBUL, June 27 (Reuters) - President Barack Obama's new pledges on curbing carbon emissions drew a cautious welcome from the U.N. climate change chief on Thursday, but she said no country was doing enough and proposed the White House appoint an energy czar to coordinate reforms.
Obama revived his stalled climate change agenda on Tuesday, promising new rules to cut carbon emissions from U.S. power plants and moves to support renewable energy.
Christiana Figueres, head of the U.N. Climate Change Secretariat, said countries were on track to agree in 2015 a policy framework to curb greenhouse gas emissions and better enable the poorest nations to adapt to climate change.
She said Obama's announcement was "very welcome" but that countries needed to do more on the issue of climate change.
"Finally the United States is putting out a menu of very concrete measures," she told Reuters at a meeting of climate change activists in Istanbul.
"But I think the fact remains that compared to what the science demands ... no country is doing enough," she said.
Obama has directed the U.S. Environmental Protection Agency to craft new emissions rules for thousands of power plants, the bulk of which burn coal and which account for roughly a third of the country's greenhouse gas emissions.
The plan was criticised by the coal industry, which would be hit hard by carbon limits, and Republicans who accused the president of advancing policies that harm the economy.
Environmentalists largely cheered the proposals and Figueres recommended the appointment of an official to oversee the changes in the United States, recently overtaken by China as the world's biggest carbon polluter.
"I do think that an energy czar in the White House would be extraordinarily helpful," she said. "There has to be someone at a high level in the White House that can actually coordinate all of this and ensure that it gets done."
It was also very important for the White House to develop the capacity to measure the effects of the reforms, she said.
"There has to be one central place where this is going to be quantified in order for the United States and the world to know what effort the United States is putting in," she added.
The United Nations is attempting to resolve disputes between rich and poor countries on sharing out the burden of curbing greenhouse gas emissions as part of a new U.N. deal, a successor to the 1997 Kyoto Protocol.
It hopes an agreement will be signed in 2015 and come into force five years later.
"That is why it is very important over the next 18 months that there is enough political space opened in every country so that federal governments can actually take the decisions that they need to take," Figueres said. (Writing by Daren Butler; Editing by Pravin Char)