Belarus’ authoritarian President Alexander Lukashenko said Tuesday his country is hosting dozens of Russian nuclear weapons and will prepare facilities for the planned deployment of Moscow’s newest hypersonic ballistic missile.

His remarks came after he and President Vladimir Putin signed a treaty last week that gave security guarantees to Belarus, Moscow’s closest ally, including the possible use of Russian nuclear weapons to help repel any aggression.

The pact follows Moscow’s revision of its nuclear doctrine, which for the first time placed Belarus under the Russian nuclear umbrella amid the tensions with the West over the conflict in Ukraine.

“I have warned all my enemies, ‘friends’ and adversaries: If you step on the border, the answer will be momentary,” Lukashenko said.

Lukashenko, who has ruled Belarus with an iron hand for over 30 years and has relied on Kremlin subsidies and support, allowed Russia to use his country’s territory to send troops into neighboring Ukraine in 2022 and to host some of its tactical nuclear weapons.

Unlike nuclear-tipped intercontinental ballistic missiles that can destroy entire cities, tactical nuclear weapons for use against troops on the battlefield are less powerful.

Russia hasn’t disclosed how many, but Lukashenko said Tuesday that his country currently has several dozen of them.

“I have brought nuclear warheads here, and not just a single dozen of them,” Lukashenko said in an apparent reference to the tactical weapons, adding that the West failed to track their deployment.

“They haven’t even noticed when we brought them here,” he added.