LONDON (Reuters) – Eurostar’s peak capacity in London has fallen by 30% due to post-Brexit checks on travellers using the high-speed rail link between Britain and mainland Europe, the train operator’s boss has said. New border checks on British citizens introduced after Brexit have caused a “significant increase” in processing times at train stations, Eurostar Chief Executive Jacques Damas told the chair of Britain’s parliamentary committee on transport in a letter published on Tuesday. Damas was responding to a request from committee chair Huw Merriman seeking details about the closure of Eur…