(Bloomberg) -- President Joe Biden hit back at Russian President Vladimir Putin, saying he would never win his war in Ukraine in a speech marking the one-year point of his invasion.

Fresh off a dramatic surprise trip to Kyiv the day before, Biden sought to deliver a first-hand account from the country, highlighting its unexpected resilience against Putin.

“I’ve just come from a visit to Kyiv, and I can report: Kyiv stands strong, Kyiv stands proud, it stands tall and most important it stands free,” Biden said Tuesday at the Royal Castle in Warsaw, Poland, delivering his remarks behind bulletproof glass before an estimated crowd of 30,000 waving Ukrainian, Polish and US flags.

“Ukraine will never be a victory for Russia,” Biden said, adding that the US and its allies would announce fresh sanctions against Moscow this week. Biden didn’t elaborate on the new penalties.

The first year of the war, which Putin launched on Feb. 24, 2022, has defied expectations as Russia failed to overrun Ukraine and Kyiv’s allies stayed largely united on providing the country with weapons and imposing sanctions aimed at crippling Moscow’s war effort. 

Biden warned there will be “hard and very bitter days” ahead as Russia prepares a counteroffensive against Ukrainian forces, but that US would continue to support Kyiv.

“The United States, together with our allies and partners, are going to continue to have Ukraine’s back as it defends itself,” the president said.

Biden is visiting the region at a critical time and delivered his speech hours after Putin vowed to press on with his war and said Moscow would suspend its observation of the New START nuclear treaty with the US. Putin spoke one year after his decision to recognize Russian-backed separatists in Ukraine’s Donetsk and Luhansk regions as independent. 

Putin in his speech accused the US and Ukraine’s allies of starting the war, a claim Biden dismissed.

“The United States and the nations of Europe do not seek to control or destroy Russia. The West was not plotting to attack Russia, as Putin said today. And millions of Russian citizens only want to live in peace with their neighbors,” he said. “This was never a necessity. It’s a tragedy. President Putin chose this war. Every day the war continues is his choice.”

US Secretary of State Antony Blinken called Russia’s suspension of the New START treaty “deeply unfortunate and irresponsible.” Upon taking office in 2021, Biden extended the nuclear treaty by five years. The State Department accused Russia last month of breaching the terms of the treaty by refusing to allow inspectors on its territory.

Biden also spoke at the Royal Castle in March 2022, one month into the war, when he called the invasion a strategic failure and surprised the world with an off-the-cuff remark suggesting he supports regime change in Russia.

“For God’s sake, this man cannot remain in power,” Biden said last year about Putin.

A White House official at the time quickly clarified that he meant Putin could not be allowed to exercise power over his neighbors or the region and that the president was not encouraging regime change.

New Fighting

Ukrainian leaders are bracing for fighting to ramp up as the weather begins to warm. 

Ukrainian President Volodymyr Zelenskiy is pleading for additional and faster weapons deliveries as his military faces more intense attacks by Russia. Ukraine’s situation remains daunting, and Russia has been pouring more troops into the eastern Donbas region. 

The Biden administration so far has committed $30 billion in military aid for Ukraine since the invasion. The US on Monday announced more support, a $460 million military aid package that includes artillery ammunition, anti-armor systems and air surveillance radar. 

The US is also set to impose further export controls on third countries aiding Russia’s war efforts and additional measures targeting key Russian sectors, as well as focusing more on preventing entities from circumventing sanctions that are already on the books.

Blinken said the US is concerned about intelligence that suggests China is considering providing lethal aid to Moscow and warned Beijing against doing so. 

He cited severe consequences for the US-China relationship but didn’t elaborate on what those would be.

--With assistance from Jordan Fabian and Josh Wingrove.

(Updates with additional quotes, background throughout)

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