The European Commission plans to present its list of “green” energy sources in January, according to internal market commissioner Thierry Breton, who said he expected it to include nuclear and natural gas.

The list, known as the EU’s “taxonomy“, will determine what sources are seen as sustainable and therefore eligible for investment under rules promoting the 27-nation bloc’s shift to a carbon-neutral future.

It was meant to have landed before the end of this year, but deep divisions between member states over including nuclear and natural gas have held it up. An EU summit last week failed to bridge the gaps.

“Nuclear power and natural gas will help us achieve our climate goals,” Breton told German newspaper Die Welt in a weekend interview.

“That is why we in the commission are to present a taxonomy that includes nuclear power and natural gas.”

He said the commission was “very close to finalising” the act that would introduce the list, with member states then having a couple of weeks to comment on it before it could be presented in mid-January.

If too few countries banded together to block the list, it would become EU law without requiring adoption by the European Parliament.

France has been pushing for nuclear — which provides more than 70 percent of its energy production — to be included along with around a dozen other countries, but they face opposition from Austria, Germany and Luxembourg.

Austrian Environment Minister Leonore Gewessler, attending a meeting of EU counterparts on Monday, said nuclear energy was not climate-friendly and “has no place in the taxonomy”.

She said if it figured in the taxonomy, “we will examine it from a legal point of view and, if necessary, we will take legal steps including legal action” to block it.

But Breton said the European Union needed to double its electricity production over the next three decades and that “is simply not possible without nuclear power”.

Eastern EU countries reliant on fossil fuels for their power such as Poland want natural gas to be on the list, at least as an interim energy source, even though Europe is dependent on Russian gas supplies.

Breton said the EU needed to be “pragmatic” on that point.

“Gas is certainly not an ideal energy source for achieving carbon dioxide neutrality… but gas is still better than coal,” he said.