The International Olympic Committee said its executive board is recommending prohibiting athletes and officials from Russian and Belarus in international competitions.

The recommendation is "to protect the integrity of global sports competitions and for the safety of all the participants," the IOC said.

Switzerland is breaking from its longstanding policy of neutrality by adopting the packages of sanctions imposed by the European Union citing Russia's continuing military invasion of Ukraine.

Switzerland, which has long been a safe haven for Russian assets, announced on Monday that it's imposing financial sanctions targeting Russian President Vladimir Putin, Russian Prime Minister Mikhail Mishustin and Russian Foreign Ministry Sergey Lavrov, and is targeting the assets of certain people and companies.

Switzerland also is imposing entry bans against individuals who have a connection to Switzerland and are linked to Putin and will be closing Swiss airspace to flights from Russia, with the exception of flights for humanitarian, medical or diplomatic purposes, officials said.

Switzerland will also extend a ban on imports, exports and investments concerning Crimea and Sevastopol, which has been in place since 2014, to the Ukrainian regions of Donetsk and Luhansk.

Swiss officials said they are partially suspending the 2009 agreement on visa facilitation for Russian nationals, and those with diplomatic passports will continue to be allowed entry without a visa in an effort to continue diplomatic talks.

-ABC News' Christine Theodorou

Senior administration officials on Monday provided more specifics on the sanctions against Russia announced over the weekend and emphasized the drastic nature of these steps, saying the "actions represent the most significant actions the U.S. Treasury has taken against an economy of this size, and assets of this size,” noting the Russian central bank is multiple times larger than Iran's or Venezuela’s.

The U.S. has put into effect sanctions on Russia's central bank that keep Moscow from accessing any of their more than $600 billion in reserves in the U.S., or in U.S. dollars in foreign countries. The sanctions also target Russia’s National Wealth Fund and the Ministry of Finance.

Officials said it was clear from the beginning of the invasion that Russian President Vladimir Putin was planning to use central bank assets to mitigate any sanctions.

“Today's announcement that prohibit transactions with the Central Bank of Russia in the national wealth fund will significantly hinder their ability to do that, and inhibit their access to hundreds of billions of dollars in assets from our actions alone, they will not be able to access assets that are either in United States or in US dollars,” officials said.

“What we've done today is not only preventing them from using those dollars in the United States, but preventing them from being able to use those dollars in other places like Europe or Japan to defend their currency and prop up their institutions. And our goal was to make sure that not only would they not have access to dollars, but also not have access to other currencies," officials said.

“Our strategy -- to put it simply -- is to make sure that the Russian economy goes backwards, as long as President Putin decides to go forward with his invasion of Ukraine,” a senior administration official said.

-ABC News' Sarah Kolinovsky, Justin Gomez

After Russian President Vladimir Putin put Russia’s nuclear deterrent forces on a state of heightened alert this weekend, a White House official confirms the U.S. has not changed its own alert level.

"We are assessing President Putin’s directive and at this time see no reason to change our own alert levels," a White House official confirmed to ABC News.

"We think provocative rhetoric regarding nuclear weapons is dangerous, adds to the risk of miscalculation, should be avoided, and we will not indulge in it," the official added.

The official also noted that, as recently as June, when President Joe Biden met Putin face-to-face in Geneva, the two leaders affirmed nuclear war is tantamount to mutually assured destruction.

The leaders said in a joint statement in June, "Today, we reaffirm the principle that a nuclear war cannot be won and must never be fought."

-ABC News' Sarah Kolinovsky

Secretary of State Antony Blinken closed his remarks to the U.N. Security Council meeting by challenging the Russian Federation to "announce today -- with no qualification of equivocation or deflection -- that Russia will not invade Ukraine, stated clearly stated plainly, to the world."

"And then demonstrate it by sending your troops, your tanks, your planes back to their various can hangars and sending your diplomats to the negotiating table," he added.

Blinken laid out how the U.S. believes Russia will attack Ukraine -- but said he would welcome being wrong and for Russia to withdraw.

"Now, I'm mindful that some have called into question our information, recalling previous instances where intelligence ultimately did not bear out," he said, apparently referring to a similar address then-Secretary of State Colin Powell famously made to the Security Council presenting U.S. intelligence to justify the Iraq War. "But let me be clear, I am here today not to start a war, but to prevent one," he said, citing allies that agree with U.S. assessments.

"If Russia doesn't invade Ukraine, then we will be relieved that Russia changed course and proved our predictions wrong. That would be a far better outcome in the course we're currently on. And we'll gladly accept any criticism that anyone directs at us," Blinken said.

He continued, "Russia can still make if there's any truth to his claim that is committed to diplomacy. Diplomacy is the only responsible way to resolve this crisis"

Blinken also said that he sent a letter to Russia's Foreign Minister Sergei Lavrov earlier Thursday proposing that they meet next week in Europe following their talks in recent weeks "to discuss the steps that we can take to resolve this crisis without conflict" and that U.S. is also proposing meetings at the NATO Russia Council and the OSC Permanent Council.

"These meetings can pave the way for a summit with key leaders in the context of de-escalation to reach understandings on our mutual security concerns," he added.