(CNN) Nearly 10 months after his invasion of Ukraine began, Russian President Vladimir Putin on Wednesday acknowledged that the conflict is "going to take a while," as he also warned of the "increasing" threat of nuclear war.
Speaking at a meeting of Russia's Human Rights Council at the Kremlin, Putin said Moscow will fight by "all available means at our disposal," in what he insists on calling a "special military operation," but also said he saw no immediate need to mobilize more troops.
"With regard to the protracted nature of the special military operation and its results, of course, it's going to take a while, perhaps," he said.
And without categorically ruling out the first use of nuclear weapons, Putin said he viewed the Russian nuclear arsenal as a deterrent rather than a provocation.
"As for the idea that Russia wouldn't use such weapons first under any circumstances, then it means we wouldn't be able to be the second to use them either -- because the possibility to do so in case of an attack on our territory would be very limited," he said.
"Nevertheless, we have a strategy... namely, as a defense, we consider weapons of mass destruction, nuclear weapons -- it is all based around the so-called retaliatory strike," he said. "That is, when we are struck, we strike in response."
The Russian leader said that the United States' nuclear weapons were located in large numbers on European soil, while Russia had not transferred its nuclear weapons to other territories and is not planning to do so, but "will protect its allies with all the means at its disposal, if necessary."
"We have not gone crazy. We are aware of what nuclear weapons are. We have these means, they are in a more advanced and modern form than those of any other nuclear country, this is obvious," he said. "But we are not going to brandish these weapons like a razor, running around the world."
Putin also said there is no need for additional mobilization of Russian troops at this point, saying suggestions for more deployments "simply do not make sense."
Out of the 300,000 men called up for Russia's partial mobilization, half are currently in Ukraine -- and of those, only 77,000 are in combat units while the rest are in defense forces or training, he said.
Meanwhile, in response to a question, he described Moscow's territorial gains as a "significant result for Russia."
In September, Putin announced the annexation of four Ukrainian regions -- Luhansk, Donetsk, Kherson and Zaporizhzhia -- in a process that violated international law.
However, Russia currently controls only 60% of the southern Kherson region. It was forced to withdraw from the regional capital of Kherson city last month in a humiliating setback, though it still controls the coastline along the Sea of Azov.
"Let's be honest, the Sea of Azov has become an internal sea of the Russian Federation. All of this is a big deal," Putin said.
In Zaporizhzhia, meanwhile, the United Nations' nuclear watchdog has repeatedly warned of the risk of a nuclear accident at Ukraine's largest nuclear plant, which has been occupied by Russian forces since March.
The Zaporizhzhia nuclear power plant been rocked by explosions in recent months amid fighting nearby, with Kyiv and Moscow blaming each other for the attacks.
Earlier this week, a Russian Foreign Ministry spokesperson appeared to rule out proposals by the International Atomic Energy Agency to create a demilitarized zone around the plant, claiming it was on "Russian territory and is fully controlled by Russia."
Putin's comments come as the war enters winter, with Russia continuing to shell eastern and southern parts of Ukraine -- and facing attacks on its own soil.
Earlier this week, Russia unleashed a wave of drone and missile attacks across Ukraine, targeting the country's energy infrastructure. Ukraine has been facing a wide assault on critical infrastructure and power sources since early October.
The recent strikes caused extensive power outages in several regions, including Kyiv and Odesa, leaving many households without electricity. Ukrainian repair teams have worked frantically to restore power across the country, but their efforts are being slowed by sub-zero temperatures and poor weather.
Meanwhile, Russia has accused Kyiv of using drones to strike military airfields far inside its territory on Monday and Tuesday -- an extraordinary breach of Moscow's assumptions that it can protect its deep interior.
Ukraine has neither confirmed nor denied responsibility for the blasts, in keeping with Kyiv's policy of official silence around attacks inside Russia or in Russian-occupied Crimea.
However, in an apparent reference to the strikes, an aide to President Volodymyr Zelensky tweeted cryptically that "if something is launched into other countries' airspace, sooner or later unknown flying objects will return to departure point."