As climate delegations from around the world leaders continue to meet for UN-sponsored climate talks in Lima, Peru this week, the head of the European Union's negotiating team on Tuesday said that if a final deal is to have the necessary strength to actually compel dramatic reductions in greenhouse gas emissions over the next thirty years, it must have binding targets and enforceable mechanisms.

"The EU is of the mind that legally binding mitigation targets are the only way to provide the necessary long-term signal, the necessary confidence to the investors ... and provide credibility in the low carbon transition worldwide," Elina Bardram, head of the EU delegation at the conference, told the Guardian's Suzanne Goldenberg.

Though the EU's position had been signaled by anonymous officials ahead of the Conference of Parties (COP20) meeting in Peru, Bardram's statement is the first time a high-ranking EU official has publicly expressed the collective bargaining position of the European bloc of nations.

Pushing for "binding" targets is a direct challenge to the United States and other large polluters who say they prefer voluntary targets and more incremental reforms as they attempt to reduce emissions.

As Goldenberg reports:

The EU appears to have toughened its stance faced with major nations which claim they could not impose economy wide targets. Bardram hinted that such positions could stall the negotiating process in the lead-up to the Paris meeting. “We don’t want to get to Paris and realise that the targets and the contributions did not add up to what we needed,” Bardram told the Guardian, adding that the EU wanted the 2015 agreement to have “legal force through robust rules, procedures and institutions, to ensure long-term certainty and accountability”. The EU’s stance is at odds with the US position which favours the ‘buffet option’, that would contain some legally binding elements but allow countries to determine the scale and pace of their emissions reductions, even if this this calls into question the aim of keeping temperature rises below 2C, the level that countries have agreed to limit warming to.

Offering background on the talks in Lima, Tim McDonnell at Mother Jones described the negotiating process at the COP20 talks as the world's "most important Mad Lib," in which nations would fill-in-the-blanks regarding the size and the nature of the commitments they're ready to make ahead of talks set for Paris next year. He writes:

The goal of the Lima talks is to set a standard for how countries will formally submit their proposed emissions pledges in preparation for next year’s big summit. You can think of it like a climate action Mad Lib, where the story outline is now being drafted in Lima, and each country will fill in its blanks (but with emissions goals instead of nouns and verbs) before Paris. One of the big debates prior to Paris will be whether developed and developing countries will be required to meet the same criteria for setting those goals, and whether the goals will be legally binding. This month’s talks will also be the first key test of President Obama’s climate pact with China, which was announced last month. The deal was important for a few key reasons. It set new carbon reductions goals: The U.S. will reduce carbon emissions 26-28 percent below 2005 levels by 2025, while China promised to peak its emissions by 2030. It includes a plan to jump-start clean energy trade between the two countries. But perhaps most importantly, it could be a powerful incentive for other countries to create their own ambitious targets.

Prior to the announcement of the U.S.-China deal, the European Union in October announced its new goals which included a 40 percent reduction in greenhouse gases and a 27 percent increase in both energy efficiency and renewable energy creation, all by the year 2030. Though clearly more ambitious than anything put forward by China or the U.S., climate campaigners pushed back on the claim that even these targets are substantial enough to address the threat of runaway climate change that scientists are now warning about.

Responding to the EU's announcement in Lima, Asad Rehman, a campaigner with Friends of the Earth, told the Guardian that none of the commitments currently on the table have requisite ambition. According to Rehman and similar critics, neither the U.S. nor the more aggressive Europeans are truly acting in accordance with the scale of the problem.

"Having a deregulated climate system, having countries just make any pledge they want is a recipe for disaster," Rehman said. "What we need is science-based rigorous regulations, it’s the only way are going to tackle this climate crisis."