MILAN, Dec 1 (Reuters) - Italian energy group Eni (ENI.MI) said on Wednesday it had taken part in a $1.8 billion funding round for a project that aims to produce clean electricity from nuclear fusion. In 2018 Eni became the single biggest shareholder in Commonwealth Fusion System (CFS), a firm set up by the Massachusetts Institute of Technology to produce energy by fusing atoms at superhot temperatures. Earlier this week the head of Eni"s Fusion Program told Reuters the company was ready to invest more in the project. As governments around the world pick up efforts to combat climate change, energy companies like Eni have launched strategies to shift from fossil fuels into cleaner energy.The new funding package will allow a pilot reactor generating more energy than it consumes to be built by 2025 and will speed up progress towards having a first commercial plant ready by the early 2030s, Eni said. "We have worked with the CFS team for these last years because we recognised that their work could transform the energy landscape," Eni CEO Claudio Descalzi said.Eni has never disclosed its stake in CFS.