WASHINGTON (Reuters) - The United States wants to broker a global agreement on climate change that would contain some legal elements but would stop short of being legally binding on an international level, the country’s top diplomat on climate change issues said.

U.S. climate envoy Todd Stern speaks with delegates as they attend session during the 19th conference of the United Nations Framework Convention on Climate Change (COP19) in Warsaw November 23, 2013. REUTERS/Kacper Pempel

Todd Stern, the State Department climate change special envoy, addressed one of the thorniest issues in ongoing talks to secure a global plan to curb greenhouse gas emissions – its legal form.

Stern said a recent proposal by New Zealand for countries to submit a “schedule” for reducing emissions that would be legally binding and subject to mandatory accounting, reporting and review offers an approach that could get the buy-in of countries like the United States that are wary of ratifying an internationally binding treaty.

The content of the schedule itself and the actions each country pledges would not be legally binding at an international level.

“Some are sure to disapprove of the New Zealand idea, since the mitigation commitment itself is not legally binding, but we would counsel against that kind of orthodoxy,” Stern said in prepared remarks.

Stern delivered a speech at Yale University on Monday outlining the U.S. vision for what a climate deal should look like that could be agreed upon by nearly 200 nations in Paris late in 2015.

The agreement would succeed the 1992 Kyoto Protocol, in which nearly all wealthy countries had signed up to legally binding emissions goals, with the big exception of the United States, which refused to become a party.

Developing nations, including the world’s top carbon emitter China, had only been obliged to take voluntary steps to curb the growth of their emissions.

“This would be meaningful indeed. Nothing like it has happened before. Certainly not Kyoto, which never applied to more than around 27 percent of global emissions,” Stern said.

A new agreement would aim to ensure both developed and developing countries are on board by requiring each country to pledge national “contributions” to a global agreement.

Under the United Nations negotiating process, countries are expected put forward proposals for their national commitments by March 2015. These pledges can be revised before a final deal is agreed in Paris later that year.

The structure of national commitments paves the way for a deal that moves beyond the Kyoto Protocol’s definitions of the differentiated responsibilities of developed and developing countries, which has hampered progress in the negotiations, Stern added.

“We need to build our new agreement looking forward, to reflect the economic, political and environmental realities of the next decade and beyond,” Stern said.

In remarks made separately on Monday, a senior White House official said the U.S. is in the process of planning how to set its emission reduction targets beyond 2020.

Its current pledge is to reduce greenhouse gas emissions 17 percent below 2005 levels by 2020.

Shaun Donovan, director of the White House Office of Management and Budget, which oversees the federal budget and regulations, said in an interview for the Oct. 13-16 Reuters Global Climate Change Summit that the U.S. is aware that its own target will have a major impact on the outcome of a global deal.

“The more that we do, the more our ability to push other countries to make bold commitments as well, particularly China. It is something we are very focused on in terms of what targets we are able to get to,” he said.

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