KYIV, Ukraine — Ukrainians vowed Friday to fight on as the world marked the first anniversary of Russia's full-scale invasion, which violently ended decades of European stability and unleashed a charged battle between autocracy and freedom.

A year after the first missiles rained down on Kyiv and other cities in the early hours of Feb. 24, 2022, Ukraine's Western backers pledged indefinite support, promising to continue the supply of weapons that helped Ukrainian forces foil President Vladimir Putin's neo-imperialist plan to subjugate his neighbor.

The war, which has killed tens of thousands on each side and displaced millions of Ukrainians, has galvanized Western powers around defending a vulnerable democracy on Europe's eastern edge, injected the NATO military alliance with a new sense of purpose, and spurred the European Union to designate Ukraine as an official candidate for membership.

It has also strained the global economy, revealed cracks in the ability of affluent nations to mobilize support from the developing world, and made Putin's position as Russia's all-powerful ruler more precarious.

President Volodymyr Zelensky on Friday hailed what he called Ukraine's "furious year of invincibility" by honoring troops with military decorations at Sofia Square in central Kyiv.

Zelensky recalled the initial moments of the war, when much of the world expected Kyiv to fall within days and U.S. officials offered to ferret him out of the city to escape assassination. He declined to go.

"That is how Feb. 24, 2022 began. The longest day of our lives. The hardest day of our modern history," Zelensky said in a video address. "We woke up early and haven't fallen asleep since."

"We did not raise the white flag, and began to defend the blue and yellow," he continued, referring to the colors of the Ukrainian national flag. "We were not afraid, we did not break down, we did not surrender . . . we fought . . . and today we have been standing for exactly one year."

But Ukraine's survival is hardly assured. Fierce fighting continued along the 600-mile front line on Friday, and Russian forces still occupy huge swaths of Ukrainian territory, including Putin's coveted "land bridge" from the Russian border to Crimea, which Russia invaded and annexed illegally in 2014.

With Putin showing no sign of relenting, people around the world voiced their outrage on Friday, as protests unfolded in Russia, across Europe, and in capitals as far away as Tokyo and Seoul.

The United States and other members of the Group of Seven nations announced new sanctions, the latest in a barrage of financial penalties, export controls, and oil and gas boycotts that have begun to dent Russia's war chest but failed to isolate it globally or cripple its economy.

The terrifying initial moments that Zelensky described have been followed by 12 months of grinding battle in which Ukrainian forces have effectively leveraged billions of dollars in Western weapons to push back against Russia's much larger, better-armed military.

The Ukrainians turned back the Russian attempt to conquer Kyiv in the spring, with the humiliating Russian retreat revealing evidence of ghastly atrocities in Bucha, Irpin and other suburbs. And in counteroffensives in the fall, the Ukrainians ousted Russian occupiers from much of the northeast Kharkiv region, and from Kherson city and some nearby areas in the south.

But while the war has revealed systemic weaknesses in Russia's armed forces, the front lines have hardened since the fall and Kremlin now controls roughly a fifth of Ukraine's vast territory, including parts of four regions - Luhansk, Donetsk, Zaporizhzhia and Kherson - that Putin claimed, illegally to have annexed.

The war has also set off a cascade of acute suffering, as civilians swept up in the fighting have been gunned down or shelled trying to escape, or bombed down in their beds, hospitals and schools.

Millions have been displaced, and countless families have been separated. Reports of widespread torture, sexual violence and forced adoptions of children sent to Russia are being compiled in a multilayered attempt to hold Russian leaders accountable, potentially for alleged war crimes and crimes against humanity.

The United Nations says it has verified more than 8,000 civilians deaths since the invasion began and many more injuries, but the true toll could be much higher. Western officials have said that military deaths stand in the hundreds of thousands.

In Bucha, where evidence of widespread atrocities against civilians during the Russian occupation hardened world sentiment against Moscow, residents gathered Friday in the Church of Andrew the First-Called to honor those who were killed.

In Kyiv, which has been spared the regular attacks that have plagued other cities, air raid sirens sounded nearly 700 times over the course of the year, the city's mayor said on Telegram, and ambulance brigades made more than 900 trips to the sites of rocket and drone attacks.

Zelensky hailed Ukrainians' sacrifice and resilience over the last year, voicing gratitude to troops, medics and volunteers. Even Ukrainian schoolchildren, he noted, were donating their pocket money toward the fight.

Zelensky spoke with leaders of the G-7 later in the day and separately held a news conference in Kyiv.

A former actor who has proven to be effective in rallying Ukrainians around the deepening fight and pushing Ukraine's partners for an ever-wider array of military aid, Zelensky has at times vowed to retake every inch of Ukrainian territory from Russia but has also signaled that the war is likely to end in a negotiated deal.

A year into the conflict, it remains unclear what sort of concessions he or Putin might accept as part of a negotiated settlement.

Across the globe on Friday, nations backing Kyiv's fight lighted up monuments with its yellow-and-blue flag or, in several cities, protested Kremlin actions by staging shows of support for Ukraine outside Russian embassies. World leaders voiced their resolve.

President Biden underscored support from the United States, by far the biggest military backer, after making a symbolically potent surprise visit to Kyiv on Monday. "A dictator bent on rebuilding an empire will never erase the people's love of liberty," Biden said on Twitter. "Ukraine will never be a victory for Russia."

The Biden administration on Friday announced an additional $2 billion in security aid for Ukraine, including more Switchblade drones, artillery rounds and laser-guided rocket systems, along with new sanctions on Russian officials and entities.

The Senate's top Republican, Mitch McConnell, issued a statement proclaiming support for Ukraine to be a "core" U.S. national interest. "It is not an act of charity for the United States and our NATO allies to help supply the Ukrainian people's self-defense," McConnell said. "It is a direct investment in our own core national interests. America is a world power with worldwide interests. Our security and prosperity are deeply intertwined with a secure and stable Europe."

The British government unveiled new restrictions on the export of "every item Russia has been found using on the battlefield to date," including radio equipment, aircraft parts and electronic items used in manufacturing drones.

French President Emmanuel Macron underscored his nation's intent to stand by Ukraine. "To solidarity. To victory. To peace," Macron tweeted.

In Russia, the Kremlin did little to register the date, which fell on an extended national holiday. Police, nonetheless, took to the streets to head off scattered protests. In cities from Moscow to Siberia, antiwar activists put up banners or laid flowers and placards at sites that have emerged as symbols of sympathy for Ukraine.

Imprisoned Russian opposition leader Vladimir Kara-Murza issued a statement criticizing Putin for unleashing "unspeakable death, destruction and grief" in his war on Ukraine. Kara-Murza was detained last year after a speech critical of the war, part of a fierce crackdown on political dissent by the Russian government.

Moscow has outlawed criticism of the military, which can lead to lengthy prison sentences, though pro-war hawks have been permitted to complain about military failures and that Russian forces have not triumphed quickly enough, or used sufficiently brutal tactics.

The war has eroded Putin's standing globally and within Russia, generating private criticism from members of the elite and from current and former officials, and speculation about his departure from power should his war failures keep piling up.

This month, a charged dispute between Russian military leaders and Yevgeniy Prigozhin, who leads the Wagner mercenary group, which emerged as a crucial part of Russia's combat power, spilled into the open over the equipping of his fighters. They have been struggling for months to capture the eastern Ukrainian city of Bakhmut.

As the war enters its second year, the role of China, the third of the "great powers" that dominate U.S. foreign policy, remains unclear. The Biden administration said this month that China was actively considering providing lethal weapons to Russia, which would represent a major blow to Washington's already tense relations with Beijing.

Ukrainian and Western officials voiced skepticism this week about a new cease-fire proposal from China.

Mykhailo Podolyak, an adviser to Zelensky, said "any 'peace plan' with cease-fire only . . . and continued occupation of territory isn't about peace, but about freezing the war, defeat, next stages of genocide." Podolyak called on Russia to withdraw to Ukraine's internationally recognized borders.

On top of the human cost of the war, Ukraine remains a nation under severe economic strain as it grapples with the effects of a massive civilian exodus, loss of key industrial assets to Russian occupation, and ongoing destruction of its infrastructure, including the power sector, by Russian airstrikes.

Facing a $38 billion budget deficit in 2023, Zelenksy's government is hoping to secure a $15 billion support deal from the International Monetary Fund, which would add to earlier U.S. and E.U. pledges of aid totaling $29 billion.

Dixon reported from Riga; Ryan, Stern and Khudov reported from Kyiv. Mary Ilyushina in Riga; Catherine Belton in London; Christian Shepherd in Taipei; Alice Martins and Kamila Hrabchuk in Bucha, Ukraine; and John Wagner in Washington contributed to this report.