Home Secretary Amber Rudd has said she is irritated with the US for releasing information about the Manchester bomber before UK police would have liked.
Ms Rudd said the British had wanted to control the flow of information to “keep the element of surprise”.
She told BBC Radio 4’s Today programme she had been very clear with Washington “that it should not happen again”.
Ms Rudd said the Manchester-born bomber Salman Abedi had already been on the radar of the British security services.
She claimed the 22-year-old, born to parents of Libyan origin, “was known up to a point” in the UK.
Ms Rudd spoke out as the government raised the terrorism threat level to “critical” – the highest possible rating – on Tuesday amid fears another attack was imminent.
She said this meant the police would have 3,800 soldiers to call on and equipment for “as long as we need them”.
The measures follow Monday night’s attack at Manchester Arena, which killed 22 and injured 59.
Information about the bomber’s identity first emerged in the US, and Ms Rudd was asked whether she would be looking at how information sharing may have resulted in the premature release of details the British police and security services had not wanted in the public domain
The home secretary told Today: “Yes, quite frankly.
“The British police have been very clear they want to control the flow of information in order to protect operational integrity – the element of surprise – so it is irritating if it gets released from other sources, and I’ve been very clear with our friends that that should not happen again.”
Pressed on whether the Americans had compromised the investigation, she said: “I wouldn’t got that far, but I can say they are perfectly clear about the situation and that it shouldn’t happen again.”