A senior US congressman who claimed communications involving Donald Trump's associates were caught up in "incidental" surveillance has said he met his source on the grounds of the White House.
The meeting came a day before US House intelligence committee chairman Devin Nunes disclosed that US spy agencies may have inadvertently carried out surveillance on the US president and his associates during a routine targeting of foreigners' communications, his spokesman said.
Mr Nunes has declined to name his source.
His spokesman, Jack Langer, said the congressman went to the White House to be near "a secure location" where he could examine the information.
Mr Nunes has been concerned that Trump associates were captured in "incidental" US surveillance of foreign targets even before Mr Trump made his baseless claims that former president Barack Obama had wiretapped him last year.