Washington has revoked the visa of the Venezuelan ambassador to the US, the state department has said.
The move comes amid a diplomatic dispute between the two countries over President Barack Obama's choice of ambassador to Caracas, Larry Palmer.
Venezuelan President Hugo Chavez had been angered by comments Mr Palmer made about the country this year.
Washington's move effectively expels Venezuela's envoy, Bernardo Alvarez Herrera.
It is not thought Mr Herrera is currently in the US but the revocation means he cannot return.
State department spokesman Mark Toner said Caracas had only itself to blame.
"We said there would be consequences when the Venezuelan government rescinded agreement regarding our nominee, Larry Palmer. We have taken appropriate, proportional and reciprocal action," he said in an e-mailed statement.
News of the revocation been carried earlier on Venezuelan sources.
Venezuela's Deputy Foreign Minister Temir Porras wrote on his Twitter account: "I can confirm. USA revoked the visa of ambassador Bernardo Alvarez."
On Tuesday, Venezuelan President Hugo Chavez, a fierce critic of the US, said: "We have denied permission to this aspiring ambassador and now the US government threatens us with reprisals.
"They will do what they want but that man is not coming here as ambassador. Anyone who comes here as an ambassador has to show respect. This is a country that must be respected."
He dared the US to cut off diplomatic ties.
"If the US government wants to expel our ambassador there, let them. If they cut off diplomatic relations, let them," Mr Chavez said on state television.
Mr Chavez has long been at loggerheads with the US, denouncing "American imperialism".
The BBC's Iain Mackenzie in Washington says it is unclear how the latest escalation will affect the two countries' tempestuous relationship.
He says the situation had shown signs of improving with the election of Barack Obama, however President Chavez later declared him to be "a great disappointment" and claimed he had "the same stench as George W Bush".
Venezuela is a major oil producer and despite its political differences with Washington remains the fifth biggest crude supplier to the US.
Mr Palmer's appointment has yet to be confirmed by the US Senate.