"I don't think this is a secret that people from the US are coming to us tomorrow, State Secretary Mr. Blinken and the Defense Secretary who are coming to us," Zelensky said.
"We will be expecting, when the security will allow, the President of the United States to come and to talk to us."
The State Department and Defense Department have not yet confirmed their visit.
A planned evacuation of civilians in the besieged southern city of Mariupol on Saturday was again thwarted by the Russian military, Ukrainian leaders said.
A humanitarian corridor to provide safe passage for hundreds of civilians trapped by fighting in the port city was planned for Saturday, Deputy Prime Minister Iryna Vereshchuk said in a Telegram post.
A small convoy of buses managed to carry women, children and the elderly out of the city on Wednesday, but Ukrainian officials said the effort was largely unsuccessful because of the lack of a genuine cease-fire.
Russian forces, they said, bombed the city all day despite agreeing to the escape corridor.
That was again the case on Saturday, according to a post on the Ukrainian Parliament's official Twitter account.
"Russian occupiers again disrupted the evacuation from Mariupol," the statement read. "About 200 Mariupol residents were going to leave, but when they arrived at the assembly point, the military told them to disperse because 'there will be shelling now.'"
Petro Andriushchenko, an adviser to Mariupol's mayor, similarly said the planned evacuation was called off by Russian military officials after evacuees were already loaded onto buses.
"Yes, once again, the Russians disrupted the evacuation," he wrote on Telegram, according to CNN. "Brazenly using the efforts of Mariupol residents to return home and the honesty of the Ukrainian army in a ceasefire to organize their own plans."
Even before the hoped-for evacuation, Vereshchuk warned of a "parallel" trap corridor.
"We have just received information that the occupiers may be trying to organize their own corridor for evacuation to Russia in parallel with us," she said. "So please be careful and vigilant. Do not succumb to deception and provocation."
A Russian military chief said Friday that Russia aimed to take control of southern and eastern Ukraine and connect the Donbas region with Crimea through a ground corridor in a new phase of the war after retreating from Kyiv region earlier this month.
Though the Russian government has claimed control of the strategic port of Mariupol, it has only partial control of southern Ukraine. Some Ukrainian fighters have held out in Mariupol's steel plant, and the Ukrainian government is still in control of Mykolaiv and Odessa.
"Despite their stated conquest of Mariupol, heavy fighting continues to take place frustrating Russian attempts to capture the city thus further slowing their desired progress in Donbas," the British ministry of defense said in an intelligence update posted to Twitter on Saturday.
"Russian forces have made no major gains in the last 24 hours as Ukrainian counter-attacks to continue to hinder their efforts," the ministry said.
Since the war began on Feb. 24, there have been 5,381 civilian casualties in Ukraine and 2,946 injured, the United Nations reported in an update Friday. More than 5.1 million refugees have fled the country, according to the U.N. High Commissioner for Refugees.
The United Nations human rights office said Friday it has seen evidence of war crimes, noting that at least 50 civilians were unlawfully killed in the town of Bucha, near Kyiv, where Ukrainian forces found mass graves.