Ursula von der Leyen pledged to present a European Green Deal within her first 100 days in office | Frederick Florina/AFP via Getty Images Von der Leyen’s climate promises run into Brussels reality Climate has risen to the top of the political agenda. But implementing new, bolder goals will be tricky.

Ursula von der Leyen’s “Green Deal” climate pledges helped get the European Parliament to approve her as the next European Commission president. Now her program is facing a reality check.

A senior Commission official and leading members of the Parliament on Thursday spelled out just how difficult it might be to make some of those promises come true.

Von der Leyen’s program poses “the very clear question ... what is the ambition the Union can really pursue between now and 2030?” Mauro Petriccione, the director general of the Commission's climate department, told the Parliament's environment committee in Brussels.

Von der Leyen pledged to present a European Green Deal within her first 100 days in office, something that helped recast the German conservative in a greener light.

She made a long list of promises: enshrining a target of the EU becoming climate neutral by 2050 into law; extending the bloc's Emissions Trading System — which currently covers the power and industrial sectors — to also include transport and buildings; introducing a carbon border tax — a levy based on a product's carbon footprint — to "ensure our companies can compete on a level playing field"; and boosting the bloc's 2030 emissions reduction target to 50 percent, if not 55 percent, from the current 40 percent.

“While the Union will most likely meet its 2020 targets, the situation across member states is uneven” — Mauro Petriccione, director general of the European Commission's climate department

But some of those ideas are going to require a major recalibration of the Commission's existing goals.

Even getting the 40 percent emissions cut accepted by EU leaders in 2014 was a major slog. But 55 percent is far, far more ambitious, and distributing the required emissions cuts across EU countries and their economic sectors including transport and agriculture is expected to involve a bloody political battle.

The EU has “all the legislation we need to achieve the target that we’ve committed ourselves to — 40 percent of emissions by 2030,” Petriccione said.

He talked of a possible boost to 45 percent, but only if countries fully implement the bloc's renewable and energy efficiency goals.

Going further runs into the problem that EU countries are already at risk of missing the bloc's existing green goals for 2030, according to draft national energy and climate plans. “While the Union will most likely meet its 2020 [energy and climate] targets, the situation across member states is much more uneven than we would have wished,” Petriccione said.

Some MEPs were similarly cautious.

Peter Liese, the environment spokesperson for von der Leyen's own European People's Party, backs her program and is in favor of pushing for a 50 percent target — but not 55 percent. “That's so ambitious that it will really only work under a lot of pain,” he said.

Similarly, it's unclear whether and how a carbon border tax would work. "We don't know that yet ... and if, it's with a lot of effort and risks," Liese said.

That's an assessment echoed by Petriccione, who spent years as a senior official negotiating trade deals for the EU before becoming the Commission's top climate official. EU rules that impact foreigners create the danger of a backlash, shown by the ongoing fight with Malaysia and Indonesia over limiting palm oil imports.

"The tax issue is going to be a politically delicate one," Petriccione said, adding: "How many risks are we going to take … for the sake of climate policy? That’s a political judgment."

Von der Leyen's plan to expand the ETS to the transport sector — an idea pushed for years by the German car industry — also raised eyebrows.

"This was a debate held five years ago, and I'm really not convinced this will work out well," said Miriam Dalli, a Maltese MEP from the Socialists & Democrats who led negotiations for the Parliament on setting 2030 carbon dioxide standards for cars and vans. "Let's not rush to move transport and buildings in the ETS."

If cars were covered by the trading system, current emissions permit prices would be too low to force carmakers to clean up their fleets, she warned, pointing to studies. "The ETS price would [need] to be astronomical to make a difference in sectors such as transport."

Petriccione was similarly cautious about broadening the bloc's carbon market. “There's no way, in my own opinion, you can replace what we're doing already in the road transport sector with the ETS,” he said.

However, all indications are that von der Leyen plans to push her green program hard.

The new Commission will “move on faster than anybody in the Commission had anticipated before. There is going to be an acceleration,” Petriccione said.

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