Energy and Clean Growth Minister Claire Perry is taking a leave of absence to look after an ill relative.
Some of her responsibilities, which include carbon budgets, international climate change, climate science and innovation, green finance, energy efficiency and heat and low carbon generation, are temporarily being taken over by Universities and Science Minister Chris Skidmore,
Other responsibilities also include energy retail markets, smart meters and smart systems, oil and gas, including shale, security of supply and energy security.
Some of them will be shared with other serving ministers in the Department for Education and the Department for Business, Energy and Industrial Strategy (BEIS) over the period of the ministerial cover.
Ms Perry thanked Prime Minister Theresa May for allowing her to take the temporary leave in a tweet.
Ms Perry was elected as MP for Devizes in 2010.