Belarusian President Alexander Lukashenko said on Friday that his military's SU-24 warplanes had been modified to carry nuclear weapons and that Minsk would react immediately if the West caused it any problems.

Lukashenko said he had agreed the move to modernize Belarusian warplanes with Russian President Vladimir Putin, the Belta news agency reported.

Belarus, a staunch Russian ally, does not have its own nuclear weapons. Lukashenko did not go into details about how a weapons transfer from Moscow, which is using Belarusian territory to mount what it calls its "special military operation" against Ukraine, might take place.

Belta cited Lukashenko as talking about a potential future threat from neighboring Poland, a NATO member, while saying he was confident that the Polish military, unlike Warsaw's politicians, understood how Minsk could respond to what he called any escalation.

His overall remarks appeared to be referring to a potential threat from the West in general.

"They (the West) must understand that if they opt for escalation no helicopters or planes will save them," Lukashenko was quoted as saying.

"Everything was ready," he said, referring to the work to modify Belarusian warplanes to carry nuclear weapons.

"It's not a good idea to escalate things with Belarus because that would be an escalation with the Union State (of Russia and Belarus) which has nuclear weapons. If they start to create problems ... the response will be immediate."