The head of the European Union's executive arm on Friday joined a growing chorus calling for sanctions on Belarus where security forces cracked down on protests against strongman Alexander Lukashenko claiming victory in a disputed election.

European Commission chief Ursula von der Leyen spoke ahead of emergency talks between the EU's foreign ministers later on Friday on applying such sanctions, which would require unanimity among the 27 countries in the bloc.

"We need additional sanctions against those who violated democratic values or abused human rights in Belarus," von der Leyen said on Twitter.

"I am confident today's EU Foreign Ministers' discussion will demonstrate our strong support for the rights of the people in Belarus to fundamental freedoms and democracy."