Dominic Raab previously served as Brexit Secretary under Theresa May (Picture: PA).
The new Foreign Secretary has discussed "key global priorities" including Iran and NATO with his American counterpart.
Dominic Raab, who was only appointed on Wednesday, spoke to Mike Pompeo over the phone, according to a statement from the US Department of State.
Talks included "countering Iran's attempts to expand its nuclear programme and strengthening the NATO alliance", the statement said.
It comes after the announcement that the Royal Navy will be escorting British ships through the Strait of Hormuz amid rising tensions with Iran.
Following his conversation with the new Foreign Secretary, Mr Pompeo tweeted: "We value our close ties with the United Kingdom as we work together to address the world’s security challenges."
Mr Raab returned to cabinet as part of Boris Johnson's overhaul which includes the appointment of former soldier Ben Wallace as Defence Secretary.
Mr Wallace's arrival at the Ministry of Defence saw Penny Mordaunt, the UK's first female Defence Secretary, return to the backbenches.