The United States says it did not request the British government detain the partner of the journalist who first reported on secret U.S. surveillance programs.
David Miranda was held for nine hours by British authorities at London's Heathrow Airport on August 18 under antiterrorist legislation.
Miranda is the partner of Glenn Greenwald who wrote for Britain's "The Guardian" newspaper on U.S. intelligence surveillance programs.
His reporting was based on leaks provided by Edward Snowden, the former U.S. intelligence contractor, who is now in Russia and faces criminal charges in the United States.
White House spokesman Josh Earnest told reporters on August 19 that the decision to detain Miranda was made solely by British officials.
"There was a heads up that was provided by the British government," he said. "Again, this is something that --- we had an indication that was likely to occur, but it's not something that we requested and it was something that was done specifically by the British law enforcement officials."
Earnest did not provide information about how far in advance British officials notified the United States that Miranda would be detained.
He also did not provide details on whether U.S. officials had obtained any material from personal items confiscated from Miranda.
Greenwald had said Miranda's cellphone, laptops, and memory sticks were confiscated.
Writing in "The Guardian," Greenwald described the detention as "despotic."
While British authorities confirmed that Miranda had been detained under an antiterrorism law, they did not further explain their actions.
A statement from "The Guardian" said it was "dismayed" at Miranda's detention and that it would be pressing British authorities for an urgent clarification.
The Brazilian government expressed "grave concern" over the detention of Miranda, Greenwald's longtime partner with whom he's in a civil union. The pair live in Rio de Janeiro.
Miranda was in transit at Heathrow while traveling home to Rio de Janeiro from Berlin, where he had met filmmaker Laura Poitras, who has worked closely with Greenwald on the Snowden files.
With reporting by AP and Reuters