'The alliance is stronger': Finland joins NATO, Russia warns of 'retaliatory measures'. Ukraine live updates

Finland formally joined the North Atlantic Treaty Organization on Tuesday, more than doubling the length of the alliance's border with Russia and drawing a warning of "retaliatory measures" from Moscow.

"Finland is stronger and safer within the alliance, and the alliance is stronger and safer with Finland as its ally," Secretary of State Antony Blinken said at a ceremony in Brussels.

Finland President Sauli Niinistö emphasized his country's desire to promote stability in Europe. Finland and Sweden began seeking expedited NATO membership – and the military support it can provide – within weeks of Russia's invasion of Ukraine more than a year ago. Sweden awaits approval.

"The era of nonalignment in our history has come to an end – a new era begins,” Niinistö said. His country’s blue-and-white flag was then raised outside NATO headquarters, the alliance marking its 74th anniversary by accepting its 31st member.

Ukraine President Volodymyr Zelenskyy tweeted congratulations to Finland on joining the "only effective security guarantee in the region amid Russian aggression."

Other developments:

►President Joe Biden and his French counterpart Emmanuel Macron on Tuesday discussed Macron's upcoming trip to Beijing to meet with Chinese leader Xi Jinping. The war in Ukraine is expected to be a major topic during the three-day state visit, scheduled to being Wednesday.

►A Russian court ordered Darya Trepova, 26, held for two months pending investigation in the death of pro-Kremlin military blogger Vladlen Tatarsky. Tatarsky, 40, died Sunday in a restaurant bomb blast that wounded 30. Russian authorities say Trepova's Ukraine handlers had her deliver the bomb to Tatarsky in a statuette.

►Russian businessman Artyom Uss, who made a daring escape from house arrest in Italy after being nabbed on a U.S. warrant for breaching Western sanctions, has surfaced in Russia. Uss, the son of the governor of Russia’s Krasnoyarsk region, said he fled because Italian courts would've bowed to U.S. pressure to extradite him.

PREVIOUS UPDATES: Finland receives Turkey endorsement to join NATO

Detained journalist Gershkovich in good health, lawyers say after first visit

Lawyers meeting for the first time Tuesday with Evan Gershkovich, the Wall Street Journal reporter who was jailed by Russian authorities last week on spying charges, said he's in good health, according to the newspaper.

Gershkovich, 31, was detained Thursday in Yekaterinburg and accused of spying for the U.S. government and trying to obtain classified information. The Journal has denied the accusations and demanded the American journalist be released.

Emma Tucker, editor-in-chief of the Journal, said Gershkovich’s family is “relieved to know we finally have contact with Evan” after the outlet previously reported a lawyer and representatives from the U.S. Embassy were denied access to him in jail. Gershkovich is being kept behind bars for two months pending an investigation and could face up to 20 years in prison if convicted.

“They said Evan’s health is good, and he is grateful for the outpouring of support from around the world,” Tucker said. “We continue to work with the White House, State Department and relevant U.S. government officials to secure Evan’s release.”

The Biden administration has said Gershkovich’s release is a top priority. He is the first U.S. correspondent since the Cold War to be detained on charges of espionage.

“These charges are ridiculous. Evan is not a spy,” White House press secretary Karine Jean-Pierre said Tuesday.

– Jeanine Santucci and The Associated Press

Russia warns of 'retaliatory measures'

The Russian Foreign Ministry issued a statement warning Finland's membership in NATO would have a "negative impact" on relations between the two neighbors. Russia "will be forced to take retaliatory measures of a military-technical and other nature" to stop perceived threats, the statement said. Details on those steps will depend on the conditions for Finland's integration into NATO, according to the statement.

"We are convinced that history will judge this hasty step taken by the authorities of this country without due regard for public opinion by organizing a referendum and a thorough analysis of the consequences of NATO membership," the statement said.

WHAT IS NATO? History, facts, members and why it was created

Russian military, Wagner mercenaries remain at odds: US official

Leaders of the Russian military and Wagner, its associated mercenary group, have been squabbling over the direction of the war in Ukraine, according to a senior Defense Department official. This comes after Wagner founder Yevgeny Prigozhin recently complained that the military is providing his thousands of soldiers with insufficient ammunition.

Battle lines in Ukraine have remained largely static, with heavy exchanges of artillery fire between Russia and Ukrainian forces backed by the U.S. and its Western allies. There has been not significant movement in recent weeks, said the official, who briefed reporters Tuesday on conditions set by the Pentagon.

The infighting among Russian commanders comes as Ukraine prepares an expected counteroffensive and the U.S. released another $2.5 billion in military aid. The official also said the Pentagon has trained about 4,000 Ukrainian troops split into brigades that will operate Stryker and Bradley armored personnel carriers. Training on U.S. Abrams tanks being sent to Ukraine has not yet occurred, the official said.

The Pentagon will also be buying trucks designed to carry 30mm guns that can shoot down Iranian drones that Russia has bought from Iran, the official said.

– Tom Vanden Brook

US to provide Ukraine with another $2.5 billion in military aid

The U.S. will send Ukraine about $500 million in ammunition and equipment and will spend more than $2 billion to buy an array of munitions, radar and other weapons in the future, Blinken said in a statement. The package includes more ammunition for U.S.-provided HIMARS – light, multiple-rocket launchers – air defense interceptors, artillery rounds, anti-armor systems, small arms, heavy equipment transport vehicles, and maintenance support "essential to strengthening Ukraine’s defenders on the battlefield," Blinken said.

"This new security assistance will allow Ukraine to continue to bravely defend itself against Russia’s unprovoked and unjustified war," Blinken said.

WHAT IS NATO? History, facts, members and why it was created

Finland's entry into NATO doubles alliance's border with Russia

Finland's move to join NATO was triggered by Russia's attack on Ukraine last year. Alarmed by the invasion, the long-neutral country applied to join in May, along with neighboring Sweden, seeking protection under the organization's security umbrella.

Finland shares an 832-mile border with Russia, and the accession into NATO delivers a major blow to Russian President Vladimir Putin, who has long complained about the alliance's expansion toward his country.

NATO Secretary General Jens Stoltenberg emphasized the strategic benefits of Finland's entry during remarks Monday, saying the country "will bring to the alliance substantial military forces – well trained, well equipped with also a large reservist army." Finland's membership will also "more than double the size of the alliance's border with Russia," Stoltenberg said.

Turkey last to ratify; Sweden still waiting

Turkey, the last country to ratify Finland's NATO membership, sent official documents on Tuesday to Blinken, clearing the final hurdle for the country's entry.

Meanwhile, Sweden, which applied for NATO membership along with Finland in May, is still waiting to win approval, something Stoltenberg expects in the coming weeks. Sweden has yet to fully implement new counter-terror legislation urged by Turkey that comes into effect June 1.

Turkish President President Recep Tayyip Erdoğan has accused Sweden of "opening its arms” to the PKK and other groups classified as terrorist organizations by Turkey.

"I'm absolutely confident that Sweden will become a member," Stoltenberg said, adding that Finland's ratification was the fastest in NATO's modern history. "It's a priority for NATO, for me to ensure that happens as soon as possible. "

What is NATO?

NATO is an intergovernmental military alliance including two North American countries – the U.S. and Canada – and now 29 European countries. It was founded April 4,  1949 – exactly 74 years ago – after the end of World War II.

With the signing of the alliance, NATO countries agreed to collective defense, meaning an attack on one ally should be considered an attack on all.

Contributing: The Associated Press

This article originally appeared on USA TODAY: Ukraine Russia live updates: Finland formally joins NATO, 31st member