Vladimir Makei, the Foreign Minister of Belarus, has died at the age of 64, state news agency Belta reported on Saturday.
Belarus President Alexander Lukashenko also expressed condolences.
“Foreign Minister Vladimir Makei has passed away suddenly,” Belta said, without giving a cause of death.
“We are shocked by the reports of the death of the Head of the Ministry of Foreign Affairs of the Republic of Belarus Vladimir Makei,” Russian foreign ministry spokeswoman Maria Zakharova posted in her Telegram channel. “Official condolences will be published soon.”
Three days ago, Makei, who has held the post since 2012, attended a conference of the Collective Security Treaty Organisation — a military alliance of several post-soviet states — in Yerevan, Armenia.
He was expected to meet Russian counterpart Sergey Lavrov on Monday.
Before the presidential elections and mass anti-government protests in Belarus in 2020, Makei had been an initiator of efforts to improve Belarus's relations with the West and had criticised Russia.
However, he abruptly changed his stance after the start of the protests, claiming they were inspired by agents of the West.
In September, he defended Belarus’s position at the UN Security Council.
“Belarus is referred to as an ‘accomplice of the aggressor’ or even a party to the conflict," he said.
"We have said and continue to say: Belarus has never advocated the war. But we are not traitors either!
"We have allied commitments, and we are strictly following and will follow the spirit and letter of international treaties to which we are parties.”
Exiled opposition leader Sviatlana Tsikhanouskaya, commenting on the minister's death, called Makei a traitor to the Belarusian people.