Ukrainian officials continue to talk up a much-anticipated counteroffensive against Russia, with the commander in chief of Ukraine's army, Gen. Valery Zaluzhny, on Saturday releasing an "informational support campaign" video venerating his military forces and promising that "the time has come to take back what's ours."

The recent warm, dry weather in southern Ukraine has raised expectations that the spring counterattack could begin soon - or may already be underway. President Volodymyr Zelenskyy and others have described the looming campaign as a make-or-break chance to show Western backers, who have provided military aid and training, that Ukraine is capable of taking back its land from Russia.

Here's the latest on the war and its effects around the globe.

Key developments

• Ukraine's counteroffensive could begin "tomorrow, the day after tomorrow or in a week," another senior Ukrainian security official, Oleksiy Danilov, told the BBC in an interview Saturday, describing it as a "historic opportunity" that "we cannot lose." An adviser to Zelenskyy, Mykhailo Podolyak, has cautioned that Ukraine would not necessarily make a formal announcement before an offensive. "This is not a 'single event' that will begin at a specific hour of a specific day with a solemn cutting of the red ribbon," he tweeted.

• Wagner troops are withdrawing from positions around the embattled city of Bakhmut, according to Britain's defense ministry. The Saturday observation aligns with comments made by the group's chief Yevgeniy Prigozhin that his troops are rebasing, to be replaced by regular Russian military forces. Ukrainian officials have also noted withdrawals from the outskirts of Bakhmut, which Russia took control of this month after a months-long battle. "Wagner forces will likely be used for further offensive operations in the Donbas following reconstituting its forces," the intelligence update from the ministry added.

• A Russian governor said two drones had caused an explosion, damaging the administrative building of an oil pipeline, early Saturday in the region of Pskov in northwestern Russia. Mikhail Vedernikov said on Telegram that the incident occurred near the village of Litvinovo; there were no casualties. The Washington Post could not independently verify his assertions. They follow reported attacks causing damage in Russian territory in recent weeks, for which Ukraine has denied any involvement.

• President Biden criticized Russia's plans to host tactical nuclear weapons in neighboring Belarus, saying his reaction to that was "extremely negative." His comments on Friday came a day after Russia's defense minister was in Minsk to sign the agreement with its ally. The European Union's foreign policy chief, Josep Borrell, also condemned the deal, warning: "This is a step which will lead to further extremely dangerous escalation."

• Lawyers for U.S. reporter Evan Gershkovich appealed a three-month extension of his pretrial detention in Russia. Gershkovich was detained in March and accused of spying, which he; rights groups; and his employer, the Wall Street Journal, have denied. The United States considers him "wrongfully detained."

Global impact

• Sen. Lindsey O. Graham (R-S.C.) said that if the United States fails to back Ukraine, it would send a signal to China about taking Taiwan. "There can be no backing off of helping Ukraine because if we fail here, there goes Taiwan," he told reporters after a meeting with Zelenskyy, Reuters reported. The Republican Party has been divided over support for Ukraine in recent months, though maintaining a tough stance on China remains a priority.

• U.S. Secretary of State Antony Blinken will travel to Sweden, Norway and Finland to discuss support for Ukraine, among other subjects, from Monday to Friday, the State Department said.

• Iran accused Zelenskyy of promoting "anti-Iranian propaganda" on Saturday, after the Ukrainian president called for Tehran to stop supplying its Shahed drones to Russia. Iran's Foreign Ministry said his comments were "in line with the . . . media war" against Iran and aimed at attracting Western arms and finances.

• Russian President Vladimir Putin told his Brazilian counterpart that Moscow is open to dialogue on Ukraine, according to Reuters. Brazilian President Luiz Inácio Lula da Silva tweeted that during the phone call he reiterated Brazil's willingness to participate in peace talks. Also on Friday, Russian Foreign Minister Sergei Lavrov told China's special envoy Li Hui that there were "serious obstacles" to peace talks, according to a statement from the Russian Foreign Ministry.

Battleground updates

• Two people died and more than 30 were injured in a Russian missile strike on the Ukrainian city of Dnipro on Friday, where a hospital was destroyed. Two children, ages 3 and 6, and several health-care workers were among those injured in the attack, which also damaged a veterinary clinic, sports complex and an educational institution, regional governor Serhiy Lysak wrote on Telegram. In his nightly address, Zelenskyy called the attack a "pure atrocity."

• Russian arms manufacturer Kalashnikov, producer of the AK-47 assault rifle, is ramping up production of kamikaze drones for the war in Ukraine. In a statement released Friday, the company's president said it would be able to increase production "several times" by next year.

• Ukraine's defense ministry alleged that Russia is planning "large-scale provocations" at the Zaporizhzhia nuclear plant. The ministry's military intelligence service made the allegations of a possible false-flag operation in a Telegram post Friday, ahead of Tuesday's planned U.N. Security Council meeting to discuss plans to ensure the safety of the facility. Russia "obviously will blame Ukraine," it said. In dueling statements, both sides accused the other of disrupting a Friday monitoring mission by International Atomic Energy Agency inspectors.

The Washington Post's Natalia Abbakumova contributed to this report.