When Belarus' leader Alexander Lukashenko meets Putin, it is after a fifth weekend of protests that he demands Lukashenko's resignation.

During Sunday's mass demonstrations around Belarus, according to the country's interior ministry, 774 people were arrested, of which 500 in the capital Minsk, where at least 100,000 people are reported to have taken to the streets.

The opposition criticizes

The opposition accuses Lukashenko of rigging last month's presidential election - which has also been questioned in large parts of the world.

Since then, thousands of regime critics have been arrested and key opposition leaders have been detained, deported or forced to flee the country.

From exile in Lithuania criticizes the leading figure of the opposition Svetlana Tikhanovskaya Putin's decision to meet with Lukashenko.

"I regret that you chose to have a dialogue with the usurper and not with the Belarusian people," Tikhanovskaya wrote on social media.

"Not legally binding"

At 2 pm Swedish time, the state-run Russian news agency Tass reported that the meeting between Lukashenko and Putin had begun.

Putin's actions suggest he has no desire for Lukashenko to be ousted from power in the nearby former Soviet state.

The Kremlin has previously said that the leaders will discuss energy and trade cooperation, the countries' strategic partnerships and the continued development of "integration processes within the Union State", a supranational organization with Russia and Belarus as members.

"I would like to remind Vladimir Putin that whatever you agree on in Sochi will not be legally binding.

The new government will review all agreements signed with the illegitimate Lukashenko ", writes Tikhanovskaya.

On Monday, UN High Commissioner for Human Rights Michelle Bachelet called for inquiries into allegations of brutal treatment by opposition figures by the Belarussian authorities.

"Given the seriousness and scope, all allegations of torture and other forms of abuse by the security forces should be documented and investigated, with the aim of bringing the perpetrators to justice," Bachelet said.