Merkel stressed “that the Belarusian government must put a stop to violence against peaceful protesters, release all political prisoners immediately and engage in a national dialogue with the opposition and society in order to overcome the crisis,” her spokesman, Steffen Seibert, said.

In its statement, the Kremlin said Putin warned Merkel against foreign interference in the ex-Soviet republic.

Putin cautioned against attempts to “interfere in the internal affairs” of Belarus, the Kremlin said. Moscow also said it expected the tense situation in its neighbour and ally to soon calm down.

Mass protests and strikes have erupted in Belarus, often referred to as Europe’s last dictatorship, following a presidential election on August 9 in which incumbent Alexander Lukashenko is accused of rigging the vote in his favour.

Lukashenko, 65, has led the Eastern European nation for a quarter of a century, tolerating little dissent. Belarus is economically dependent on Russia for support.

Police have responded to the protests with a violent crackdown and thousands of demonstrators have been detained, with many of those released saying they were mistreated or even tortured while in custody.

On Tuesday, Belarus’ ambassador to Slovakia stepped down after having expressed solidarity with the protest movement, according to reports by Belarusian news portal Tut.by and Slovakian media.

Ambassador Igor Leshchenya said it was a “logical step” after having stood up against Lukashenko in a video message over the weekend.

“I stand in solidarity with those who peacefully protested on the streets and in the cities of Belarus to make their voices heard,” the ambassador said in his video.

Slovakian Prime Minister Igor Matovic has offered Leshchenya asylum in case he would not be able to return to his home country.

The head of the European Council scheduled an emergency leaders summit on Wednesday to discuss the crisis. Last week EU foreign affairs ministers agreed to begin preparing sanctions against Belarusian officials responsible for police violence and election fraud.