Romania and Bulgaria will be partially integrated into the Schengen area of free movement in March 2024, the European Council announced on Saturday.
Romania and Bulgaria, both members of the EU bloc since 2007, were rejected at the end of 2022 from the vast Schengen zone, within which more than 400 million people can travel freely without internal border controls.
Their applications were initially vetoed by Austria, which had for years said it had to host a disproportionate number of undocumented immigrants as a result of poorly protected external Schengen borders.
On Saturday, the 27 EU member states agreed unanimously to lift controls at the two countries' air and sea borders as of March 31, according to a statement from the European Council.
Discussions over opening the land borders will continue next year.
The European Commission welcomed the two countries' partial Schengen inclusion, which comes after 12 years of negotiations.
"An enlarged Schengen area will make the EU stronger as a Union, internally and on the global stage," it said in a statement.
Commission President Ursula von der Leyen called it a "historic moment".
"Today is a day of great pride for Bulgaria and Romania," she said in a post on social media. "They both deserve it. They will make Schengen even stronger."
The Schengen area was created in 1985 and includes 23 of the 27 EU member states, as well as their associated neighbours Switzerland, Norway, Iceland and Liechtenstein.