Belarusian President Alexander Lukashenko. AFP
"Your convincing victory in the elections clearly testifies to your high political authority and to the undoubted support of the population for the state policy Belarus is pursuing," Putin said, according to the Kremlin.
Chinese leader Xi Jinping also congratulated Lukashenko on winning a seventh term in office, Beijing's state media said.
"Xi Jinping sent a congratulatory message to Lukashenko on his re-election as President of Belarus," state news agency Xinhua said.
Lukashenko,70, appeared to have won 87.6 per cent of the vote, according to an official exit poll.
Exiled opposition leader Svetlana Tikhanovskaya called the election a "farce", while the EU described it as a "sham".
Lukashenko, however, said he did not care whether or not the bloc recognised the results.
And he had "no regrets" over letting his "older brother" Russian President Vladimir Putin's troops enter Ukraine through Belarus in 2022.
In Sunday's election victory, he won more of the vote than in 2020, when he won 81.04 per cent.
Belarus's 2020 election ended in nationwide protests with demonstrators accusing Lukashenko of rigging the vote.
Tens of thousands of Belarusians fled their country in the aftermath of the 2020 protests as the KGB embarked on a repression spree, mainly to neighbouring Poland and Lithuania.
Lukashenko said Sunday his opponents were behind bars or abroad out of choice.
"Some chose prison, some exile," he said.
"If it is prison then it's those who opened their mouths too widely," he added.
Repenting and asking for pardon were preconditions for any prisoner releases, he said during a news conference that lasted four hours and 25 minutes.
In Warsaw, home to many exiled Belarusians, opposition leader Tikhanovskaya described Lukashenko as a "criminal who has seized power".
In a statement Sunday, foreign ministers of the eight Nordic-Baltic nations -- Estonia, Latvia, Lithuania, Denmark, Finland, Iceland, Norway and Sweden -- saluted "the tireless efforts of the Belarusian democratic forces led by Svetlana Tikhanovskaya".
The United Nations estimates that some 300,000 Belarusians have left the country since 2020 out of a population of nine million.
They will not be able to cast ballots, with Belarus having scrapped voting abroad.
In the run-up to the election, the Lukashenko administration pardoned around 200 political prisoners.
Known as "Europe's last dictator" -- a nickname he embraces -- Lukashenko's Belarus has retained much of the Soviet Union's traditions and infrastructure.
If he completes his term, which will finish in 2030, he will have been in power for 36 years.
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