Responding to Russia's accusation that the U.S. was behind Wednesday's drone attack on the Kremlin, White House spokesperson John Kirby said it was a "ludicrous claim."

"There's a word that comes to mind that I'm obviously not -- not appropriate to using on national TV," Kirby said on CNN on Thursday.

"I will just tell you Mr. Peskov is lying, and I mean, that's obviously, it's a ludicrous claim," he added. "The United States had nothing to do with this. We don't even know exactly what happened here, Kaitlin. But I can assure you, the United States had no role in it whatsoever."

Kirby said the U.S. does not have any information on who is behind the strike but are "trying to learn more about this as best we can."

-ABC News' Justin Gomez

Russian President Vladimir Putin's spokesman accused the United States of being involved in the drone attack on the Kremlin on Wednesday.

"We understand well that the decision about such terror attacks are taken not in Kyiv, but in Washington," Dmitry Peskov told reporters in a briefing. "Often targets are determined not in Kyiv but in Washington. They don't Kyiv the right everytime in choosing the means. In Washington they also clearly understand that we know that."

He added, "Without question. Such decisions -- the determining of targets and means -- are all dictated to Kyiv from Washington."

Peskov said it was important that Washington understand the "danger" of such involvement in an attack.

-ABC News' Patrick Reevell

Russian forces launched a "complex air strike" with "drones and missiles" on Kyiv early Thursday morning, the Kyiv City Military Administration said on Telegram.

The air raid siren went off in Kyiv for three and a half hours during the attack, the Kyiv City Military Administration said.

There were no casualties or injuries from the strikes.

"According to preliminary information, all the missiles and UAVs were destroyed," the Kyiv City Military Administration added.

This was the third attack on the capitol in four days, the administration said.

-ABC News' Natalia Kushniir

The U.S. Embassy in Ukraine sent an alert to Americans on Wednesday warning of an "ongoing heightened threat of missile attacks," including in Kyiv.

"In light of the recent uptick in strikes across Ukraine and inflammatory rhetoric from Moscow, the Department of State cautions U.S. citizens of an ongoing heightened threat of missile attacks, including in Kyiv and Kyiv Oblast," the alert stated.

The U.S. Embassy urged U.S. citizens to follow guidance from local authorities and to observe air alarms and shelter appropriately.

During his annual Victory Day speech in Moscow's Red Square on Tuesday, Russian President Vladimir Putin claimed that the Ukraine war was "unleashed" on Russia and blamed "Western global elites" while calling Ukrainian President Volodymyr Zelenskyy a puppet.

Putin also directly compared his ongoing war in Ukraine to the Soviet Union's victory over Nazi Germany in 1945, which is what Victory Day commemorates. He claimed that Russia "once again" was fighting for "civilization" and he painted a topsy-turvy picture that Moscow wants peace with all nations.

"Today, the civilization is once again at a decisive, turning point and an actual war has been unleashed against our homeland again," Putin said. "But we fended off international terrorism, we will protect residents of Donbas too and ensure our security."

Putin's speech made clear once more that the Russian president has no intention of negotiating currently or scaling back his ambitions to defeat Ukraine.

However, the Victory Day military parade in Moscow was a significantly shrunken version of itself on Tuesday, compared with previous years, due to Russia's huge losses in Ukraine and its urgent need for equipment. There appeared to be approximately 50 military vehicles taking part in this year's event compared with 130 during the 2019 parade. Tuesday's parade was also comprised of nearly all high armored vehicles, similar to Humvees.

The flypast part of the event, which usually involves helicopters and fighter jets, was cancelled on Tuesday despite clear, sunny skies in the Russian capital. But perhaps what was most notable was the cancelling of the parade in at least 24 Russian cities due to security concerns that Ukrainian forces might be able to strike them, likely because of Russia's shortages of troops and equipment.

-ABC News' Patrick Reevell