BRUSSELS: The European Union must stop importing diamonds from Russia, five of the bloc’s 27 countries said in a joint proposal seen by Reuters, as the EU prepares new sanctions against Moscow for waging war against Ukraine.

The EU, which has so far implemented six rounds of sanctions since Russia invaded Ukraine on Feb. 24, needs unanimity to agree any such ban that Belgium - home to the world’s biggest diamond trading hub Antwerp - has rejected in the past.

The bloc was spurred into fresh action after President Vladimir Putin ordered a partial military mobilisation last week and moved to annex parts of eastern Ukraine.

The EU’s executive European Commission is expected to present a formal proposal for more sanctions to member states this week.

Poland, Ireland, Lithuania, Estonia and Latvia proposed introducing a retaliatory ban on imports of diamonds from Russia, where Alrosa is the world’s largest producer of rough gems. The Antwerp World Diamond Centre said sanctions would take away some 30% of business and benefit rival trade hubs, adding clients should be allowed to decide themselves if they wanted Russian gems.

Belgium’s foreign ministry and the diplomatic representation to the EU did not respond to requests for comment.