Ukrainian President Volodymyr Zelensky says he is on his way to Washington, where he will meet with US President Joe Biden on Wednesday.
This is his first foreign visit since the Russian invasion in February.
The White House also confirmed the trip and said it would supply Ukraine with a battery of Patriot missiles, which would significantly increase the country’s air defense capability.
Tuesday marked 300 days since Russia’s invasion of Ukraine.
Mr. Zielinski will also address Congress and hold several bilateral meetings.
“I’m going to America to strengthen Ukraine’s resilience and defense capabilities,” he wrote on Twitter.
Mr Zelensky regularly hosts foreign leaders in the capital Kyiv and has visited troops around Ukraine. He paid an unannounced visit to the frontline city of Bakhmut on Tuesday.
Ukraine’s president has also spoken frequently to world leaders by telephone and video call – often from his office in Kyiv.
But the unannounced visit to a foreign country is the first since the war began and is a sign of the importance of Ukraine’s relationship with the United States, which has played a key role in providing military aid.
The new Patriot missile system promised by the US will enable Ukraine to protect its critical infrastructure against Russian attacks. Ukrainian officials have long appealed to the West for a more powerful air defense system.
Russia is targeting Ukraine’s energy sector, plunging millions of people into darkness during a winter with temperatures several degrees below freezing.
In its briefing ahead of Mr Zelenskiy’s visit, the White House also confirmed a new security aid package for Ukraine worth around $2bn (£1.6bn).
Work is also underway to advance a bill that would see Ukraine receive more than $40bn (£33bn) in additional funding in 2023.
In terms of total spending on direct military assistance since the beginning of the conflict, the United States has done more than any other country.
President Zelensky has appealed for more money – saying the monthly defense costs for Ukraine were about $5 billion ($4.1 billion).
His visit comes a day after Washington made an unannounced visit to the frontline town of Bakhmut, where Ukrainian and Russian forces have been fighting for months.
The President said that he met the soldiers and distributed awards to the soldiers.
The visit was a significant show of defiance – and a show of support for Ukrainian forces engaged in some of the heaviest fighting in recent weeks.
