The privacy rights of air passengers travelling from Europe to the US will be put at risk by an information- sharing deal between the two aimed at stopping terrorist attacks, the European Union’s top data protection official has said.

Peter Hustinx wrote in a letter that the agreement, to be unveiled on Friday, could violate the rights of EU citizens. It allows the US to retain information about passengers for 15 years, up from three at present, while placing “no limitation to what US authorities are allowed to do with the data”, Mr Hustinx wrote on Wednesday to Wolfgang Schäuble, the German interior minister who clinched the deal.