The Guardian reports that the leaders of Germany, the Netherlands, Belgium, Luxembourg and Denmark have written to Ursula von der Leyen and António Costa urging closer EU-UK ties, especially on clean energy and Britain's return to the EU's internal electricity market, ahead of a Brussels summit. The letter's signatories include Friedrich Merz and Mette Frederiksen, and Energy UK has estimated Britain could pay £10bn in extra costs from 2024 to 2029 if the current energy relationship stands.