Mike Pompeo has said the US will not pull its diplomats from Venezuela after the South American country’s president ordered that they leave within three days.
Nicolas Maduro broke diplomatic relations with the US after Donald Trump decided to recognise the Venezuelan opposition leader Juan Guaido as interim president.
But Secretary of State Mr Pompeo said the Mr Maduro does not have the legal authority to sever relations with the US, and that diplomats would not be removed.
Mr Pompeo said the US would abide by Mr Guaido's directive, which is that countries retain their diplomatic missions in the South American country.
Other nations, including Canada, Brazil and Argentina, also have recognised Guaido as Venezuela's president.
Announcing the break in relations, Mr Maduro told a crowd of supporters gathered at the presidential palace: "Before the people and nations of the world, and as constitutional president.....I've decided to break diplomatic and political relations with the imperialist US government.”
He made the announcement after a day that saw Juan Guaido, the head of the opposition-controlled congress, declare himself interim president.
The move was immediately backed by President Trump's administration.
It said it was willing to use all its economic and diplomatic power to restore Venezuela's democracy.
Mr Maduro said in his speech the US was making a "grave mistake" by trying to impose a president on Venezuela.
