U.S. citizens who have been vaccinated against coronavirus with one of the EU-approved vaccines could visit the European Union in the summer, European Commission President Ursula von der Leyen has not ruled out.

"It is my understanding that Americans are using vaccines approved by the European Medicines Agency," von der Leyen said, noting the "tremendous progress" of the United States in vaccinating the population. "This will make free travel and travel to the European Union possible," the EC head added.

She stressed that all 27 EU member states will accept those vaccinated with drugs authorized by the European regulator.