Day 29 of the Russian move on the Ukraine…One month…No Russian victory…NATO talks…More US troops for NATO countries?

The removal of Russia from the G20 would be a potent symbolic step that would deny Russia a seat at the table with the world’s largest economies at a time when Moscow has already been shattering decades of ties with the west.

The president’s comments, at a news conference on Thursday, came after he and the leaders of 30 other nations participated in back-to-back summits of NATO and the Group of 7, and just before a third summit, with the European Union. All three meetings were aimed at expressing solidarity in confronting Russia’s invasion of Ukraine.

Ejecting Russia would echo the 2014 decision of the G8, a smaller group of the world’s largest economies, after Russia’s invasion and seizure of the Crimean peninsula from Ukraine.

President Volodymyr Zelensky of Ukraine appeared via video link at the closed-door NATO meeting that started the day and made another urgent plea for help. “I am sure you already understand that Russia does not intend to stop in Ukraine,” he said, according to a transcript of his remarks released by the Ukrainian government. “Does not intend and will not. It wants to go further.”

In other major developments:

• Outgunned Ukrainian forces are several days into a counteroffensive that has scored some successes. On Thursday, the Ukrainians claimed to have added to their momentum by destroying a Russian landing ship at a southern Ukrainian port in Russian-occupied territory that Russia has said was important to their efforts to supply their troops.

• Concern is rising among Western leaders that Mr. Putin may turn to unconventional weapons as its advance in Ukraine falters. NATO allies agreed on Thursday to provide the country with equipment and training to deal with the fallout from any possible Russian use of chemical, biological or nuclear weapons, and NATO said it was increasing its own preparedness for such an event.

• The United States hit Russia with a new round of sanctions on Thursday, targeting more than 300 members of its Parliament and dozens of defense companies, while moving to restrict Russia’s ability to use gold reserves to prop up its currency. The actions came in conjunction with new sanctions from Western allies.

• The Moscow Exchange resumed partial trading on Thursday for the first time in nearly a month. The index rose 4 percent, probably buoyed by government policies aimed at avoiding a sell-off.

• The United States will take in 100,000 Ukrainian refugees and donate $1 billion to help European nations deal with the surge of migrants, a person familiar with the decision said. More than three million Ukrainians have poured into Poland and other countries, and, according to the United Nations children’s agency, more than half of Ukraine’s children have been displaced.