The EU on Tuesday ruled out forcing US and Canadian citizens to get visas after making progress on a row over permit-free travel for five of the bloc's countries.
Citizens of Bulgaria, Croatia, Cyprus, Poland and Romania all need visas to enter the United States. Canada maintains visa restrictions on Bulgarians and Romanians.
The European Parliament in March urged the European Commission, the EU's executive arm, to force US citizens to get visas to enter the union in retaliation.
But European Union migration commissioner Dimitris Avramopoulos said they made headway in talks with Washington and Ottawa.
"The EU will always choose engagement, commitment and patient diplomacy over any form of unilateral retaliation," he told a news conference.
"Because this is in the mutual interest of both EU citizens, as well as the citizens of the US in this case," he said.
On Canada he said it had allowed a "considerable number" of Bulgarians and Romanians in without visas since Monday after "sustained diplomatic efforts."