Russia-Ukraine updates: US sanctions Russian military shipbuilder, diamond miner

The United States is slamming Russia's plans to reopen its stock market for limited trading on Thursday for the first time in a month since Russian forces invaded Ukraine.

"What we’re seeing is a charade: a Potemkin market opening," White House deputy national security adviser Daleep Singh said in a statement early Thursday. "After keeping its markets closed for nearly a month, Russia announced it will only allow 15% of listed shares to trade, foreigners are prohibited from selling their shares, and short selling in general has been banned. Meanwhile, Russia has made clear they are going to pour government resources into artificially propping up the shares of companies that are trading."

"This is not a real market and not a sustainable model—which only underscores Russia’s isolation from the global financial system," he added. "The United States and our allies and partners will continue taking action to further isolate Russia from the international economic order as long it continues its brutal war against Ukraine."

Shares plunged and the Moscow Exchange was shut down following Russia's invasion of Ukraine on Feb. 24. The heavy restrictions on trading as the exchange opens Thursday morning aim to prevent the kind of massive selloff that took place last moth in anticipation of crushing financial and economic sanctions from Western nations, according to The Associated Press.

-ABC News' Molly Nagle

A team set up by the White House has been gaming out worst-case scenarios in Ukraine, mostly focused on the possibility Russia carries out chemical and biological attacks, according to a National Security Council official.

The so-called "Tiger Team," set up at the request of national security adviser Jake Sullivan in late February after Russia's invasion of Ukraine began, has analyzed the possibility of Russia using nuclear weapons, but the NSC official emphasized that is not the team's focus. The official said the group is mostly focused on protecting supply chains, security operations of U.S. personnel and planning for chemical or biological weapon attacks.

U.S. officials have repeatedly warned that Russia may be considering using chemical weapons in Ukraine and say Russian allegations that Ukrainians were developing chemical weapons may be a pretense to use such weapons themselves.

-ABC News' MaryAlice Parks

There have been over 60 attacks on health care facilities since Russia invaded Ukraine, according to the World Health Organization, which said it "condemns these attacks in the strongest possible terms."

WHO has verified 64 such incidents between Feb. 24 and March 21 -- about two to three attacks per day -- resulting in 15 deaths and 37 injuries, the organization said in a statement Wednesday assessing the impact of the war on Ukraine's health infrastructure.

"Attacks on health care are a violation of international humanitarian law, but a disturbingly common tactic of war -- they destroy critical infrastructure, but worse, they destroy hope," Dr. Jarno Habicht, WHO representative in Ukraine, said in a statement. "They deprive already vulnerable people of care that is often the difference between life and death. Health care is not -- and should never be -- a target."

Among other health care impacts amid the war, many hospitals are limiting primary health care and essential services to focus on treating the wounded, it said. Nearly 1,000 health facilities are also close to conflict lines or in seized areas, and about half of the country's pharmacies are believed to have closed, according to WHO.

"The consequence of that -- limited or no access to medicines, facilities and health professionals -- mean that treatments of chronic conditions have almost stopped," it said.

Additionally, 1 in 4 Ukrainians have been "forcibly displaced" by the war, "aggravating the condition of those suffering from noncommunicable diseases," the organization said.

-ABC News' Christine Theodorou

The United Nations Security Council defeated a resolution put forward by Russia on the humanitarian crisis in Ukraine.

In a symbolic gesture, 13 members of the U.N. Security Council on Wednesday abstained from voting on the resolution, which made no mention of Russia's role in creating the crisis and had been roundly criticized by members. Only Russia and China voted in favor.

No country voted against it, including the veto-wielding United States, United Kingdom or French envoys.

"To be honest, it was not necessary to veto, and I don't think the resolution that was put before us was worthy of the U.S. using its precious veto power," U.S. Ambassador Linda Thomas-Greenfield said.

-ABC News' Conor Finnegan