Poland urged the European Union on Thursday to do more to curb volatile prices in the EU carbon market, which it said are driven by financial speculators and have burdened businesses. EU country leaders met in Brussels for a summit to discuss issues including soaring energy prices, but the energy section of the talks was paused in the afternoon as countries could not agree on issues including their response to high carbon prices. Speaking before the summit, Poland"s Prime Minister Mateusz Morawiecki criticised fluctuating CO2 prices, which he said benefited mainly speculators. "ETS prices should be fairly constant and reasonably predictable, not in spikes," Morawiecki said, adding that the Polish government had proposed changes regarding the carbon market to the European Commission. Europe"s benchmark carbon price soared to a record high of 90.75 euros per tonne last week, having increased by more than 50% since the start of November amid rising gas prices and the looming expiry of ETS options. The CO2 price started the year at roughly 31 euros per tonne. A draft of the leaders" summit conclusions, seen by Reuters, said countries would invite the European Commission to "deepen the examination of the functioning of the electricity markets, as well as supervision of EU ETS trading". Countries did not agree on that wording, and EU officials said Poland, the Czech Republic and a handful of other countries had sought stronger wording on curbing the role of speculators in the system. Spain has also called for speculative activity to be restricted in the ETS in recent months. The carbon market is the EU"s core policy for cutting greenhouse gas emissions causing climate change. It forces power plants and factories to buy a permit for each tonne of CO2 they emit, and the Commission has proposed expanding the scheme to cover shipping and impose higher CO2 costs on airlines. An preliminary investigation by the EU securities watchdog last month said there was no proof of abuse in the carbon market. Its full report is due by early 2022. read more Reporting by Kate Abnett, Jan Strupczewski; editing by David Evans Our Standards: The Thomson Reuters Trust Principles.