The very fact that the Belarusian leader said that NATO and/or Ukraine’s dispatch of “small units” to his country wouldn’t cross his red line suggests that he expects that it might occur in the near future. As long as this isn’t “full-blown aggression” that sees their “troops…cross the border and start a (larger) war”, then he wouldn’t request the use of Russia’s tactical nukes in response to Belgorod-like scenarios.
"...he wouldn’t request the use of Russia’s tactical nukes in response to Belgorod-like scenarios."
What, you mean, like an adult (wouldn't ask)?
"...Russia hasn’t resorted to those means..."
What, you mean, like an adult?
(Покажи мне, кто твой друг...)