The EU is likely to sanction between 15 and 20 individuals for their role in electoral fraud and a crackdown on protesters in Belarus, a senior official said Tuesday.

The bloc has been preparing asset freezes and travel bans over the crisis that has unfolded in the ex-Soviet republic and after an emergency video summit last week EU Council President Charles Michel said a "substantial number" of people would be targeted.

The European Union is trying to find ways to get strongman President Alexander Lukashenko to listen to the unprecedented protests that followed his hotly disputed August 9 re-election, which the bloc has rejected as not free or fair.

EU foreign ministers meeting for informal talks in Berlin on Thursday and Friday are expected to give political approval to a list of targets, before the list is formally approved soon afterwards. 

Asked how many names were on the list, a senior EU official said it would likely be "something between 15 and 20", but the final total would depend on legal verification carried out by the EU's lawyers.

Because sanctions listings can be challenged all the way up to the European Court of Justice, the EU subjects each one to rigorous checks to make sure they are legally watertight.

European leaders including Michel, French President Emmanuel Macron and German Chancellor Angela Merkel have all sought to persuade Russia to help bring about a peaceful conclusion to the Belarus crisis.

The senior EU official said the "very interesting tango between Russia and Belarus" in recent years, in which Lukashenko has resisted Russian President Vladimir Putin's efforts to get him to join a political-economic union, had disrupted the Moscow-Minsk dynamic.

After drifting away from Putin, Lukashenko was now suddenly seeking his support, the official said, complicating European efforts to get Putin to encourage the Belarus leader to start talking to the opposition.

"Is Putin usefully prodding Alexander Lukashenko in the way of this dialogue? My answer has to be no -- he is in a different business," the official said.