Greece and eleven eastern and central European countries have demanded the European Union strengthen a fund that helps poorer EU nations transition to clean energy, a letter seen by Reuters showed, as Brussels prepares to ‌overhaul the bloc’s biggest climate change policy.

The European Commission is preparing a revision of the EU emissions trading system (ETS) and is fielding competing demands from governments and industries over how to amend the huge scheme. The Commission proposal is due on July 15.

In a letter to the European Commission dated June 19, the 12 governments urged the EU to strengthen the “modernization fund” – a ⁠pot of revenues from carbon market permit sales, which has invested more than €20 billion since 2021 to help the EU’s poorest member states wean themselves off fossil fuels.

“In the current political and economic context, characterized by increased geopolitical risks and uncertainty, predictable financing mechanisms remain an essential condition for the success of the energy transition in the EU,” said the letter.

“We call for a significant increase in the scale of financing, aligned with the growing challenges of the transition.”