Sam Allardyce has left his post as England manager by mutual agreement with the Football Association after one match and 67 days in charge.
It follows a newspaper investigation claiming he offered advice on how to “get around” rules on player transfers.
Allardyce, 61, is also alleged to have used his role to negotiate a deal worth £400,000 to represent a Far East firm.
An FA statement said Allardyce’s conduct “was inappropriate” and Gareth Southgate will take temporary charge.
“He accepts he made a significant error of judgement and has apologised,” the FA said.
“This is not a decision that was taken lightly but the FA’s priority is to protect the wider interests of the game and maintain the highest standards of conduct in football.
“The manager of the England men’s senior team is a position which must demonstrate strong leadership and show respect for the integrity of the game at all times.”
Allardyce succeeded Roy Hodgson in July following England’s disastrous performance at Euro 2016 in France and becomes the national side’s shortest-serving full-time manager.
