Ukrainian President Volodymyr Zelensky plans to visit Washington on Wednesday. It is reported that he may meet US President Joe Biden.
It will be his first foreign visit since the Russian invasion in February.
Officials, speaking on condition of anonymity, told US media that Zelensky could address Congress.
The tour or plan is officially confirmed.
In a letter Tuesday, Democratic House Speaker Nancy Pelosi urged members of Congress to attend Wednesday night.
“Please attend for a special focus on democracy,” he wrote, without elaborating.
Zelensky regularly hosts foreign leaders in the capital, Kiev, and visits troops around Ukraine. He made an unannounced visit to the frontline town of Bakhmu on Tuesday.
Ukraine’s president has spoken frequently with world leaders by telephone and video call from his office in Kiev.
But the unannounced visit to a foreign state would be the first since the war began and would signal the importance of Ukraine’s relationship with the United States, which has played a leading role in providing military aid.
In terms of overall spending on direct military assistance since the beginning of the conflict, the United States has pledged $18.5 billion, more than any other country (as of November 20).
President Zelensky appealed for more funding. He said Ukraine’s monthly defense spending is about $5 billion.
More recently, US media reported that President Joe Biden’s administration is considering supplying Ukraine with Patriot missiles that would enable the country to protect its critical infrastructure from Russian attacks.
Russia continues to target Ukraine’s energy sector, plunging millions into darkness with winter temperatures several degrees below freezing.
On Tuesday, President Zelensky made an unannounced visit to the frontline town of Bakhmu, where Ukrainian and Russian forces have been fighting a fierce battle for months.
The President said he met the soldiers and awarded the soldiers.