Mikhail Kasyanov said Friday that he believes Putin was "misled" by advisers about the state of Russian forces and how long an invasion would take.
The programme's guest claimed that Ukraine President Zelensky posted a photo on Russia's Victory Day of a Ukrainian soldier wearing a Nazi symbol.
Other rumors that Russia's president is suffering from some kind of ailment have raised questions about who might succeed him.
A Russian city marked Victory Day with a "Shoot the last fascist" event, which saw a child in a military uniform shoot a Nazi soldier effigy with an air rifle.
The man speaking to Putin during the parade was alleged to be Dmitry Kovalev, though this has not been officially confirmed.
The most famous crime couple in American history made a surprise appearance during Victory Day celebrations in Russia.
"Putin is perverting history, changing history—or attempting to change it, I should say—to justify his unprovoked and unjustified war," Jen Psaki said.
A Russian Foreign Ministry spokeswoman said she knows who is responsible for the attack on Russia's ambassador to Poland.
Putin defended his decision to invade Ukraine as the "only right solution" during a speech he gave to commemorate the Victory Day celebrations Monday.
"Grooming if I ever saw it," said one comment below the viral video. "They obviously don't know about drones and javelins."
Some observers questioned why Putin was wearing a blanket during the Victory Day festivities, while others suggested the president was limping at the event.
"The occupiers celebrate Victory Day on the bones of Mariupol," the city council said.
The new International Space Station commander made the patriotic WWII speech as Russia's invasion of Ukraine continues.
Thousands of military units and personnel paraded in Moscow's streets to mark Russia's annual celebration of its victory over Nazi Germany in 1945.
"On your hands is the blood of thousands of Ukrainians and their hundreds of murdered children. TV and the authorities are lying. No to war," the message said.
A video shows Sergey Andreev's face covered in the red substance, shortly after he attempted to lay a wreath at the cemetery of Soviet soldiers in Warsaw.
"There was a threat that was growing day by day. We had do something…it [invasion] was the only right solution we could take," Putin said.
U.K. Defense Secretary Ben Wallace will urge the world to call out the "absurdity" of Russian generals in a speech at the National Army Museum in London.
Russia had already notably scaled back its May 9 Victory Day celebrations compared with previous years, amid the Kremlin's ongoing war with neighboring Ukraine.
A statement from the Kremlin issued Sunday said Russian forces are "fighting shoulder to shoulder for the liberation of their native land from Nazi filth."
Ukrainian President Volodymyr Zelensky compared Russia's actions in Ukraine to those of Nazi Germany during World War II on Sunday.
Veterans who fought alongside Russians against Nazi Germany have urged Vladimir Putin to release Ukrainians from a besieged steel plant in Mariupol.
Konstantin Sivkov suggested the government control "all strategic resources...like land, factories and everything else" in a video viewed widely Saturday.
Days before Russia's annual Victory Day celebration, Ukrainian forces reclaimed five areas in the Kharkiv region.
On Monday, Russia celebrates Victory Day, its annual commemoration of the end of World War II. But the war in Ukraine might dampen the festivities.
The Kherson region has been almost entirely under the control of Russian forces since the beginning of March.
A search by Newsweek on a local recruiting website found more than a dozen job adverts hiring recruits in mobilization training.
Vladimir Putin may announce a new phase of his Ukraine invasion during Russia's annual Victory Day celebrations—or may say nothing of note.
The Russian president is likely to "desire to have a symbolic success in Ukraine" before the upcoming May 9 Victory Day commemorations, the U.K. said.
Russian forces intend to hold a "parade on the bones of Mariupol citizens," an adviser to the city's mayor said.