Ahead of the one-year anniversary of Russia's invasion, US President Joe Biden said he was visiting the Ukrainian capital to express Washington's "unwavering" support.
US President Joe Biden on Monday made a surprise visit to the Ukrainian capital, just days ahead of the first anniversary of Russia's invasion of Ukraine.
"Joseph Biden, welcome to Kyiv! Your visit is an extremely important sign of support for all Ukrainians," Ukraine's President Volodymyr Zelenskyy said on social media.
Air raid sirens sounded across Kyiv shortly before the news was confirmed.
The visit, which had not been announced in advance for security reasons, was Biden's first trip to Ukraine since Moscow launched the war.
Ukrainian lawmaker Oleksiy Goncharenko said Biden was meeting with Zelenskyy as air raid sirens were heard in the capital.
The two leaders visited the Wall of Remembrance of the Fallen for Ukraine in Kyiv.
What did Biden say?
"As the world prepares to mark the one-year anniversary of Russia's brutal invasion of Ukraine, I am in Kyiv today to meet with President Zelenskyy and reaffirm our unwavering and unflagging commitment to Ukraine's democracy, sovereignty, and territorial integrity," Biden said in a statement.
The White House said Biden would announce the delivery of further equipment to Ukraine, including artillery ammunition, anti-armor systems and air surveillance radars. Biden said the new military aid package was worth $500 million (€468 million).
Washington will later this week announce more sanctions against individuals and companies linked to "Russia's war machine," the White House said.
Biden also delivered remarks at Kyiv's Mariinsky Palace. "One year later, Kyiv stands. And Ukraine stands. Democracy stands,'' Biden said.
Biden to visit Poland
The White House had announced earlier this month that Biden would travel to Poland on February 20 for a two-day visit, raising speculation that the US president would also visit Ukraine.
Poland is seeking more US troop presence in its territory.
On Sunday, Polish Prime Minister Mateusz Morawiecki said he and Biden would discuss the possibility of increasing US troop presence in Poland and making it more permanent.
"We are in the process of discussion with President Biden's administration about making their [troop] presence more permanent and increasing them," Polish Prime Minister Mateusz Morawiecki told broadcaster CBS.
Last June, Biden had said the US would set up a new permanent army headquarters in Poland in response to Russian threats.
Biden is due to meet with Polish President Andrzej Duda and top Eastern European officials.
Latest Western leader in Kyiv
Biden is the latest Western leader to travel to Kyiv since the start of Russia's war.
In June, German Chancellor Olaf Scholz, French President Emmanuel Macron and then Italian Prime Minister Mario Draghi traveled together by night train to Kyiv to meet with Zelenskyy.
British Prime Minister Rishi Sunak also visited Kyiv shortly after taking office last year.
In the weeks leading up to his visit, the White House had denied that Biden would head to Ukraine, even after the Poland visit was announced.
On Friday, White House National Security Council spokesman John Kirby was asked by a reporter if Biden's trip would include more stops beyond Poland. "Right now, the trip is going to be in Warsaw," he replied.
The visit marks Biden's first to a war zone as president. Former US presidents including Donald Trump, Barack Obama and George W. Bush had made surprise visits to Afghanistan and Iraq during their time in office.
Biden said he had visited Kyiv six times when he served as vice president. "I knew I would be back," he said.