Did Belarusian President Alexander Lukashenko decide to break off ties with Russian President Vladimir Putin? No, that's not true: The video fragment was taken from Lukashenko's speech during VI All Belarusian People's Assembly in February, 2021.
When giving the speech, Lukashenko referred to the opposition initiative "Intensive reform package for Belarus," which lists the goals of the opposition political organizations, including withdrawal from the Union State, exiting Collective Security Treaty Organization (a military alliance in Eurasia that includes Russia, Armenia, Belarus, Kazakhstan, Kyrgyzstan and Tajikistan), withdrawal of Russian military objects from the territory of Belarus and reinstatement of border control with Russia.
The claim appeared in a video (archived here) where it was published by 70jrutjml9y on May 18, 2023. It opened:
17.05 Urgent. Lukashenko ends relationship with Putin. Security services proved Lukashenko had been poisoned!!!
This is what the post looked like on TikTok at the time of writing:
(Source: TikTok screenshot taken on Thu May 25 09:02:12 2023 UTC)
At the time of this writing, the Belarusian president was attending the Supreme Eurasian Economic Council in Moscow, where he was scheduled to have a bilateral meeting with Russian President Putin.