Biden urges the international community to punish Russia for its attempt to annex land in Ukraine

On Friday, President Joe Biden issued a statement in which he condemned Russia’s purported annexation of Ukrainian territory. In response to Moscow’s most recent escalation, the United States has imposed a number of sanctions and issued a warning to President Vladimir V. Putin that the United States will defend “every single inch” of NATO territory against any potential attack.

A few hours after Mr. Putin delivered a speech in which he asserted Russian rule over four eastern Ukrainian districts, Mr. Biden referred to the conduct as a “fraudulent” breach of international law that shown “contempt for peaceful countries worldwide.”

The additional sanctions imposed by the Biden administration are intended to severely impair Russia’s military and technology sectors, as well as other businesses, and to further cut off the ability of senior leaders and their families to engage in global trade. Among these people are a pair of governors from Russia’s central bank.

Officials in the United States have long held the concern that Vladimir Putin may escalate the conflict by either launching a conventional military strike against sites in Eastern European countries like Poland and Romania, which are both NATO allies and which serve as transit points for weapons into Ukraine, or by launching cyberattacks against those countries.

The current wave of sanctions makes good on longstanding promises made by the administration of former President Joe Biden to penalise any effort by Russia to annex conquered territory in Ukraine. However, the United States has had difficulty growing the number of countries that are part of the coalition that is helping Ukraine. Meanwhile, a number of other world powers, most notably China and India, have maintained strategic partnerships with Russia and continue to enrich it through the purchase of energy.

If Mr. Putin decided to be more specific about his threats to use nuclear weapons, that may transform the situation. Mr. Putin has said that Russia would use all means possible to safeguard its territory, and some commentators have speculated that he may apply this threat against Ukrainian military moves in the territories that he has unlawfully acquired. Mr. Biden has strongly cautioned Mr. Putin against making use of nuclear weapons, and some of Mr. Biden’s advisers have expressed their confidence that other global leaders are communicating the same message to Moscow.

Mr. Sullivan told reporters that “there is a possibility, given all of the loose rhetoric and the nuclear saber-rattling by Putin,” that Putin may give serious consideration to launching a nuclear attack after Mr. Putin made a threatening reference to the use of nuclear weapons in his presentation. According to the opinions of several analysts, this would most likely be implemented in the form of a relatively small nuclear weapon designed for tactical use, either on the battlefield or as a warning shot in an unpopulated region.

In spite of Mr. Putin’s most recent action, the administration of President Biden is not yet ready to take the drastic step of placing sanctions on foreign buyers of Russian energy. Officials in the United States are apprehensive of sending energy prices rising higher, particularly soon before midterm congressional elections and as Europeans become more irritated about the cost of electricity for their homes.

Mr. Putin admitted that President Xi Jinping of China had “questions and worries” about the conflict at the beginning of a meeting that took place at a summit last month in Samarkand, which was located in the country of Uzbekistan. And according to officials from the United States, Beijing, which is Moscow’s most powerful partner, has abstained from providing material assistance to Russia for the conflict.