The United States has expelled three Venezuelan diplomats, in response to the expulsion of three of its own consular officials from Caracas.
Just over a week ago, Venezuela had accused the expelled Americans of having links with violent groups.
President Obama said the claims were baseless and false.
At least 13 people have been killed during weeks of protests in Venezuela, although the opposition puts the number of dead at 15.
The US State Department said Ignacio Luis Cajal Avalos, Victor Manuel Pisani Azpurua, and Marcos Jose Garcia Figueredo were considered "personae non-gratae" and had 48 hours to leave the country.
On 16 February, Venezuela said it was expelling three US diplomats for allegedly meeting students who had been involved in violent marches.
But the US State Department soon rejected the accusations in an official press statement, followed by remarks by the President, Barack Obama.
'Legitimate grievances'He told reporters after a meeting in Mexico that Venezuela had been "making up false accusations" and that the government of President Nicolas Maduro should focus on the "legitimate grievances of the Venezuelan people."
Consular officials Breann Marie McCusker, Jeffrey Gordon Elsen and Kristopher Lee Clark were accused of meeting students in private universities in the last two months.
Washington's diplomatic reprisal came on the same day the Venezuelan government named a new ambassador to the US.
Foreign Minister Elias Jaua said the move illustrated Caracas' willingness to maintain a political and diplomatic rapport with Washington, reports BBC Mundo's Thomas Sparrow in Washington.
On Tuesday, Mr Jaua said Mr Maduro had named Maximilian Arvelaez as the country's new envoy to the US. Mr Arvelaez was previously the ambassador to Brazil.
The recent unrest started in Tachira and the neighbouring state of Merida, when students took to the streets, angered by Venezuela's high crime rate and economic woes, including record inflation and shortages of some staples.
But the government has blamed the shortages on "saboteurs" and "profit-hungry corrupt businessmen".
President Maduro accused opposition leader Leopoldo Lopez of inciting violence, but his arrest triggered further demonstrations.
The government blames Mr Lopez for the unrest and accuses him of conspiring against the government with the US Central Intelligence Agency (CIA).
There have also been large rival demonstrations by supporters of the government.
President Maduro has called for a "national peace conference" to be held on Wednesday.