The most senior US diplomat in Britain condemned media leaks of an investigation into a suicide bomb which killed 22 people in Manchester, saying the US government would take action to identify those responsible.
"These leaks were reprehensible, deeply distressing. We unequivocally condemn them," Lewis Lukens, US charge d'affaires in London and acting ambassador to Britain, said on BBC radio on Thursday.
"The United States government is launching an investigation into these leaks and will take appropriate action once we identify the source of the leaks," he said. "We are determined to identify these leaks and to stop them."
British Prime Minister Theresa May said on Thursday she would tell US President Donald Trump that intelligence shared between their two countries had to remain secure.