The United States has expelled three Venezuelan diplomats, a week after Venezuela expelled three U.S. diplomats it accused of conspiring with student protesters.
The State Department said Tuesday the envoys have 48 hours to leave the U.S.
Venezuela and the United States have not had ambassadors in each other's countries since 2010, although they have maintained embassies.
Despite the latest tensions, Venezuela is expected to name a new ambassador to the U.S.
Venezuelan President Nicolas Maduro said Monday he is selecting an ambassador to improve dialogue with the United States and because Americans think Venezuelans "are killing each other."
Three weeks of anti-government protests in Venezuela have left at least 14 people dead and about 150 injured. The demonstrations are the biggest challenge to Mr. Maduro since he took power last April.
Venezuela has accused the United States of meddling in its internal affairs, while the U.S. has expressed its own concerns about the leftist government of Mr. Maduro and his predecessor, the late Hugo Chavez, including its ties to countries such as Iran, Russia and Cuba.
The anti-Maduro protesters say the president's socialist-inspired policies have led to shortages of basic goods and inflation above 50 percent, despite the country's vast oil reserves.
Mr. Maduro, meanwhile, accuses opponents of trying to stage a U.S.-backed coup.