The head of Russia's notorious mercenary group Wagner posted a video to social media on Monday that he claimed showed him flying on a fighter jet that had just completed a bombing sortie over the city of Bakhmut, the epicenter of fighting in eastern Ukraine.
In the very dark video, Prigozhin appeared to be inside a plane flying in darkness, wearing a helmet and a pilot mask.
"We are landing, we bombed Bakhmut," the businessman and Kremlin ally said.
Prigozhin also challenged Ukrainian President Volodymyr Zelensky to fight him in the skies over Bakhmut, saying he would board a Mig-29 fighter jet the next day.
"If you have the will, we will meet in the skies. If you win, you will take Artemovsk [the Russian name for Bakhmut], if not, we will go until the Dnipro [River]," Prigozhin said.
Earlier on Monday, Ukraine's parliament adopted a resolution condemning Wagner, whose mercenaries are fighting alongside Russian troops, as a terrorist organization.
"We are preparing to destroy Wagner as a component of international terrorism," the head of the Ukrainian presidential administration, Andriy Yermak, said.
He said the recognition was a "step towards bringing [Wagner] to justice."
Wagner mercenaries are taking part in Moscow's offensive on Bakhmut, which Russia has been trying to capture for months, with heavy losses on both sides.
Ukraine's defense in the area has been weakened by recent Russian territorial gains, in particular the town of Soledar further north.
Zelensky vowed to fight for Bakhmut "as long as we can" on Saturday.
Prigozhin said that "fierce battles are going on for every street".