European Commission president Ursula von der Leyen has taken charge of a soon-to-be-published list of sustainable investments amid controversy around the possible classification of fossil gas and nuclear energy as “green” or “transitional” activities under certain conditions, according to several sources familiar with the process, according to Euractiv.com.

The European Union is moving closer to integrating nuclear power and natural gas into the bloc’s sustainable finance taxonomy – a set of rules designed to provide investors with a common definition of what is green and what is not in order to channel more capital into sustainable businesses.

The list of activities that Europe considers “green” or “transitional” investments will be laid down in a so-called ‘delegated act’ adopted by the European Commission setting out detailed implementing rules under the EU’s sustainable finance taxonomy regulation, adopted in December 2019.

But after several failed attempts and mounting controversy over the role of gas and nuclear power in the energy transition, President von der Leyen has now taken matters into her own hands, several sources told EURACTIV.

“It is possible that the Delegated Act will be presented to the college [of commissioners] next week,” said Pascal Canfin, a leading lawmaker who chairs the European Parliament’s powerful environment committee.

“The matter is now in the hands of Ursula Von der Leyen,” he told EURACTIV.

On Wednesday evening, the EU passed the first part of its taxonomy rulebook, setting out environmental criteria for investments including renewable energy, shipping and car manufacturing that will apply as of January 2022.

But no decision has been taken yet on the most politically sensitive part of the taxonomy, dealing with gas and nuclear investments.