US President Barack Obama has revealed he is nominating a top Defence Department official to become the US ambassador to Saudi Arabia.
In a White House statement on Wednesday, Obama said he would nominate Joseph William Westphal, who has been undersecretary of the Army since 2009, US media reported.
The diplomatic post is one of the most critical for the US and comes as tensions increase between the two historic allies, particularly over policy toward Syria, Iran and Egypt.
Saudi Arabia’s recent rejection of a rotating seat on the UN Security Council was seen by many commentators as being a deliberate act against recent US policies.
Later, the head of Saudi Arabia's intelligence agency, Prince Bandar Bin Sultan Al Saud, said his country was distancing itself from America, describing the move as a "major shift".
An American official later told the Wall Street Journal, "our interests increasingly don't align".
The US has since sent Secretary of State John Kerry to Saudi Arabia to help smooth over tensions.