About 4,000 opposition supporters gathered in Minsk, the capital, Sunday to mark the formation of the Belarusian People's Republic in 1918, which lasted a few months until the Soviets entered the country.
"We will not give them the country, and we will hit back at those who have the nerve to roll back the current developments," said Alexander Lukashenko.
Lukashenko, dubbed "Europe's last dictator" by Washington, was officially reelected for a third term in March. Western nations, including the United States, called the elections fraudulent and introduced sanctions against the country and travel bans on some Belarusian officials, urging Lukashenko to release political prisoners and improve his human rights record.
The opposition led by presidential candidate Alexander Milinkevich protested the results of the elections in central Minsk, trying to repeat the "orange and rose revolutions" of Ukraine and Georgia. The rally was soon dispelled and Milinkevich was briefly arrested.
The charismatic 52-year-old president, who has support in his homeland for maintaining relative stability in comparison with some other former Soviet republics, also dismissed rumors that he had a heart attack and a stroke, and said he and his family were in good health.
"We will outlive the opposition, which is spreading rumors on the Internet that someone in my family has died or is on the deathbed," Lukashenko said, adding that he did have some health problems and was rather tired.
"But I did not miss hockey training," he said. "And I knew everything that was happening in the country."