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.

After some missed calls, President Joe Biden finally connected with the parents of Wall Street Journal reporter Evan Gershkovich, White House press secretary Karine Jean-Pierre confirmed Tuesday.

"He felt it was really important to connect with Evan's family," she told reporters on Air Force One as the president travels to Ireland.

Meanwhile, National Security Council spokesperson John Kirby said Gershkovich's detention is "pretty fresh" and officials are still trying to get consular access to Gershkovich, which they have not been able to do.

He would not get into any specific conversations the U.S. is having with Russians about releasing Gershkovich or if a prisoner swap is a possibility.

"I just want to make a couple of things clear that is, the determination of wrongful detention, it doesn't start the clock necessarily on communicating with the Russians about getting him released," Kirby said. "We're very early in this process here and I certainly, I think you can understand why I wouldn't talk about any discussions we might be having with the Russians about his release or Paul [Whelan]'s release. We certainly wouldn't do that."

Kirby said the administration is "certainly having discussions about what we can do to get him released."

"I don't want to go into details about these internal deliberations, having things out in the public sphere viscerally might actually make it harder to get Evan and Paul home, and that's what we're focused on," Kirby said.

-ABC News' Justin Gomez