Airports in Sofia and Bucharest today lifted passport controls for those arriving from or departing for most EU member states as Bulgaria and Romania partially joined the EU’s free movement zone, Schengen.

The two countries reached an agreement late last year to join the Schengen zone by air and sea as Austria opposed their full membership — which does not yet include land travel — saying Romania and Bulgaria needed to do more to prevent illegal immigration.

The outgoing government’s interior ministerKalin Stoyanovtold reporters today that Bulgaria is expected to become a full Schengen member by the end of the year, meaning that border checkpoints will be abolished for people and goods traveling by road or rail.

For his part, the Romanian prime minister said that the country expects to complete land border negotiations this year.

The President of the European Commission, Ursula von der Leyen, in a statement she welcomed this development, calling it “a great success for both countries” and said that “together we are building a stronger, more united Europe for all our citizens”.

Bulgaria and Romania have joined a regional police force along with Austria, Greece and Slovakia to deal with the migrant flow.

The EU’s European Border and Coast Guard Agency (Frontex) is responsible for cooperation between national border guards and the border guards of Schengen member states. Last month it announced it would triple the number of officers in Bulgaria to help deal with the number of people crossing into the bloc from Turkey.