There is currently no threat to Russia that would call for the use of nuclear weapons, President Vladimir Putin said Friday.

Speaking at the St. Petersburg International Economic Forum, Putin said the use of nuclear weapons is only possible in "exceptional cases" and that he does not believe "such a case has arisen."

But he repeated a warning made days earlier that Moscow "reserves the right" to arm Western adversaries as a response to some NATO allies allowing Ukraine to use their weapons to strike targets inside Russia.

"If they supply (weapons) to the combat zone and call for using these weapons against our territory, why don’t we have the right to do the same?" Putin asked.

"But I’m not ready to say that we will be doing it tomorrow, either," Putin added, suggesting that it might affect global stability.

He didn’t specify where such arms might be sent.

The United States and Germany recently authorized Kyiv to hit some targets on Russian soil with the long-range weapons they are supplying to Kyiv.

On Wednesday, a Western official and a U.S. senator said Ukraine has used U.S. weapons to strike inside Russia under newly approved guidance from President Joe Biden that allows American arms to be used for the limited purpose of defending Kharkiv, Ukraine’s second-largest city. The official was not authorized to comment publicly on the sensitive matter and spoke on condition of anonymity.

Putin made the comments during a question and answer session with a pro-Kremlin moderator at the forum, which has been used by Russia for decades as a showcase for touting the country’s development and to woo investors.

Earlier in a speech, he said the Russian economy is growing despite heavy international sanctions and said Moscow has growing economic ties with countries in Africa, the Middle East and Asia.

Putin said Russia "remains one of the key participants in world trade," despite the fact that the country is under sweeping sanctions that were imposed for sending troops into Ukraine and cut off much of Russia’s trade with Western Europe, the U.S. and their allies.

The main driver of Russia’s economic growth is the fighting in Ukraine - now as important to the Kremlin economically as it is politically.

Russians are finding a few imported staples, and most global brands have disappeared - or been reincarnated as Russian equivalents. But not much else has changed economically for most people, with massive state spending for military equipment and hefty payments to volunteer soldiers giving a strong boost to the economy.