MOSCOW — Russian President Vladimir Putin on Thursday blamed the West for soaring tensions over Ukraine, suggesting the United States and its allies to respond to Moscow’s demands quickly, NBC News reported.

At his annual end-of-year news conference, the Russian leader said it was up to the US and NATO to swiftly provide the security guarantees Moscow demanded last week, though he insisted he doesn't want a fresh armed conflict.

“The ball is in their court,” Putin told the more than 500 Russian and foreign reporters in attendance at the marathon event. “They need to respond to us with something.”

Speaking to senior military officials on Tuesday, Putin said Russia would respond "adequately" to any Western aggression and would develop its army further.

"Why did they expand NATO and renounce the missile defense treaties? They are to blame for what is happening now, for the tensions building up in Europe," Putin said.

Russia has massed some 100,000 troops along the Ukrainian border, prompting fears of an invasion as early as next month, but has repeatedly denied that it has any plans to attack its neighbor.

Putin sounded optimistic about the response to the security demands issued by the Kremlin last week, which called for NATO to halt its eastward expansion as well as for legally-binding security guarantees that certain offensive weapons will not be deployed to Russia's neighboring countries.

The Russian leader said Washington appeared ready to begin negotiations around its proposals early next year in Geneva, though it is unlikely the US and its allies will give the guarantees he wants.

Moscow wants unconditional guarantees of its security now and in the future, and won’t accept the expansion of NATO eastward to include Ukraine, he said.

He scorned the US for inching closer to Russia's “doorstep,” and added that sometimes it seems Moscow and the West live in “different worlds.”

The Russian president appeared to lose his cool when confronted over Moscow’s aggression in Ukraine, according to Reuters.

After a reporter for Sky News asked whether Moscow could give security guarantees and promise not to invade its neighbor, Putin exploded: “You are demanding guarantees from us? It’s you who should give us guarantees. Immediately. Right now. And not talk it over for decades.”

Secretary of State Antony Blinken said earlier this week that Washington was working with its European allies to address what he called “Russian aggression” with diplomacy, but said President Joe Biden opposes the kind of guarantees sought by Putin.

Biden warned Putin in a virtual call earlier this month that Russia will face “severe consequences” if it attacks Ukraine.

Putin was also asked about his country's emerging alliance with China. He noted that China and Russia are increasing trade with one another, collaborating on human rights and tackling climate change.

Perhaps more alarmingly for some Western observers, he said that "China has one of the most advanced technological armies and we are working with them to develop high precision weaponry."

Putin has held the marathon event, where he answers questions on a range of subjects, every year since he became president in 2001. Since 2004, each news conference has been at least three hours long, with the longest coming in last year at 4.5 hours.

The Russian president appeared eager to speak about his domestic agenda, saying "let's not get bogged down in the international agenda... let's go to the regions," before taking questions from local media.

Naturally, many of the questions focused on Russia's response to the Covid-19 pandemic and fears over the Omicron variant.

Putin said that he hopes Russia will reach up to 80% herd immunity in 2022. He said that the current level of 59.4% collective immunity in the country is insufficient.

"This refers to both our citizens who have recovered and who were vaccinated. Here, about 70 million got the first vaccine, about 70 million-plus got two injections, but this is not enough," he told reporters.

When talking about the threat posed by the Omicron variant, Putin added that the pandemic cannot be solved without global vaccine distribution.

"I am talking about the need for mutual recognition of vaccines and the distribution of these vaccines around the world as quickly as possible and in as large quantities as possible, otherwise we will not cope with this problem globally, humanity will live with it all the time and suffer huge losses," he said.

Before Putin addressed the media Thursday, Russia's Covid death toll passed the 600,000 mark, according to a Reuters tally. The country has struggled to contain cases and has the third-highest death toll in the world, with low vaccination take-up harming its ability to emerge from the pandemic. — Agencies