'Gringos' now need visas - Maduro
Venezuela is to shrink US embassy staff numbers, limit the activities of diplomats and require American citizens to apply for visas to bask on the nation's beaches.
Speaking before a crowd that rallied to protest against imperialism, President Nicolas Maduro said "gringo" meddling had forced him to adopt the measures, which include requiring US diplomats to seek approval from the Foreign Ministry for meetings they conduct in his country.
Relations between the two nations have been deteriorating rapidly as Maduro blames US plotting for the host of economic and social woes plaguing the socialist-governed country.
He recently accused America of working with local opposition groups to stage a coup that involved bombing the presidential palace, a claim Washington said was ludicrous.
The two countries have not exchanged ambassadors since 2010, but have diplomatic staff working at their respective embassies.
Mr Maduro told the rally the US had far more staff in Venezuela than his government had in America and addressed President Barack Obama directly, saying he had "arrogantly" refused to engage in conciliatory talks.
"I'm very sorry, Mr President, that you have gone down this dead end," he said during the speech all Venezuelan television and radio stations were required to carry.
Mr Maduro said he was imposing the new tourist visa requirement for national security reasons, saying that in recent days authorities had detained several US citizens who he claimed were involved in espionage, including a pilot.
Earlier, Venezuela released four missionaries from North Dakota detained several days ago for unknown reasons. They were banned from coming back for two years.
Venezuela will charge Americans the same tourist visa fees that the US charges Venezuelans and it will require payment in dollars, which are increasingly scarce in Venezuela.
Mr Maduro said all comers would be welcome - except for a few selected US officials, including former president George Bush and Republican senator Marco Rubio of Florida.
The move could have a bigger impact on business travellers than holidaymakers. As one of the world's largest oil producers, Venezuela remains an important destination for executives and the new restrictions could affect US companies investing there.
A senior administration official in Washington said the US government had not received any communications from Venezuela and could not comment on the new restrictions .
"We are aware of reports that President Maduro repeated a number of inflammatory statements about the United States during a televised political rally. The continued allegations that the United States is involved in efforts to destabilise the Venezuelan government are baseless and false," the official said.
Americans have been staying away from Venezuela as crime has soared, exchange rates have become difficult to navigate and Mr Maduro has stepped up attacks on the US government.
Just 36,000 US citizens visited in the first nine months of 2014, about half the number that visited two years earlier, according to Venezuela Tourism Ministry data. Overall, 950,000 foreigners visited Venezuela last year.
Mr Maduro also announced that he was cancelling a trip to Uruguay, where he had been expected to celebrate the inauguration of a fellow leftist politician as president, citing the "political situation" in Venezuela.
Venezuelans took to the streets of Caracas in dueling demonstrations, with one group calling attention to a crackdown on government opponents and another showing support for the embattled socialist administration.
Government supporters marched to the presidential palace to express their rejection of imperialism and commemorate the 26th anniversary of a convulsion of violence in Caracas widely seen by government backers as evidence of the brutality of pre-socialist administrations.
Opposition activists, meanwhile, gathered to condemn the arrest of Caracas mayor Antonio Ledezma earlier this month and the death on Tuesday of a teenager shot during an anti-government protest.
In San Cristobal, where the 14 year old was killed during an anti-government protest, thousands of people massed in the streets of the Andean town known for sparking the country's protest movements.