Venezuela rescinded an invitation to European Union observers to monitor the presidential vote in July.
The country's electoral authority cited EU sanctions against Venezuela for their decision on Tuesday.
"They are not worthy people to come to this country...while they maintain sanctions," Elvis Amoroso, the head of the National Electoral Council (CNE), said in a statement on state television.
The EU called on the National Electoral Council to reconsider its decision.
Why is Venezuela under EU sanctions?
The EU introduced sanctions against Venezuela in 2017.
The bloc has imposed restrictions on Venezuelan officials, including travel bans, asset freezes, and an embargo on arms over a deterioration of democracy, the rule of law, and human rights.
The EU temporarily lifted sanctions against four officials linked to the electoral body, including Amoroso, to promote free and fair elections on July 28.
Shortly afterward, however, the government-controlled legislature approved a measure to ask the CNE to revoke the invitation for EU electoral observers, leading to Tuesday's decision.
EU sanctions are colonialist and "coercive, unilateral and genocidal," Amoroso said in the statement.
The EU office in Caracas said it "deeply regrets" the CNE's decision, saying elections should take place transparently and be supported by international observation.
The Community of Latin American and Caribbean States (CELAC), the Caribbean Community (CARICOM), a panel of experts from the United Nations, the African Union and the Carter Center, among others, will attend as observers, Amoroso added.
Maduro squashing opposition
President Nicolas Maduro is running for his third term, while former diplomat Edmundo Gonzalez represents a major opposition coalition.
Maduro's government reached a deal with the opposition last year to hold elections with international observers present.
Since then, however, the Supreme Court, loyal to Maduro, upheld a 15-year ban on opposition primary winner Maria Corina Machado.
The opposition argues this ban is based on trumped-up accusations, and several other opposition leaders and activists have been arrested.
In April, the United States re-imposed sanctions on the oil industry, saying the government had not done enough to ensure the electoral process was fair.
lo/rmt (AP, AFP, dpa, Reuters)