"These weapons will be a legitimate target of the Russian army acting in the context of the special operation," he said in an interview broadcast on Monday.

Lavrov also told state television that "NATO is, in essence, going to war with Russia through a proxy, and it is arming that proxy. War means war."

Lavrov also saw the possibility that the conflict would escalate to include the use of nuclear weapons, although he used a tone of hope about the prospects for a peace agreement.

Speaking to Russia's Channel One, he said that Moscow wants to avoid the "artificial" increased risks of such a conflict.

"This is our main position on which we build everything. The stakes are now high," Lavrov said.

"I don't want to artificially increase these risks. A lot of people want to. The risk is real and we should not underestimate it."

                                    "Good Actor"

Lavrov also accused Ukrainian President Volodymyr Zelensky of "pretending" to negotiate, calling him a "good actor".

"If you watch what he says carefully and read carefully, you will find thousands of contradictions," the top Russian diplomat said.

The Russian foreign minister said last week that Moscow was committed to avoiding a nuclear war.

On Twitter, Ukrainian Foreign Minister Dmytro Kuleba said on Monday that Lavrov's recent comments were an indication that Russia had lost its "last hope of intimidating the world from supporting Ukraine."

"So talking about a 'real' danger of World War III. It just means that Moscow feels defeated in Ukraine."

Days after the invasion began on February 24, Russian President Vladimir Putin ordered his nuclear forces to be put on alert.

The United States and its NATO allies have said they do not want direct military intervention in Ukraine, in order to avoid the risks of a third world war.