Vitalii Mazurenko, a Ukrainian journalist and deputy editor-in-chief of the Polish outlet Obserwator Miedzynarodowy, was dismissed after insulting Polish President Karol Nawrocki, according to the outlet's statement published on Aug. 27, The Kyiv Independent reports.

The news comes amid rising tensions between Ukraine and Poland, a country that, since the start of the full-scale invasion, has been one of Kyiv’s key allies.

Earlier this week, during a live broadcast on the Polsat News, Mazurenko called Nawrocki "pachan," a slang term used in criminal circles to describe a gang leader or crime boss.

In a follow-up statement, the media outlet said that Mazurenko’s comment reflected his personal opinion and did not represent the position of the publication.

"As a Polish portal, we strongly reject and do not tolerate any undermining of the authority of the President of the Republic of Poland," the statement read.

Under Polish law, publicly insulting the president is a criminal offense punishable by up to three years in prison.

Mazurenko, who is originally from Ukraine but holds Polish citizenship, later apologized for his remarks. Nevertheless, Zbigniew Bogucki, head of the Polish President’s Office, called for legal action to be taken against him.

"Polish citizenship should be a unique honor and an obligation to put Poland and its interests first," Bogucki said.

The official suggested that this case may be a reason "to start a serious discussion" about introducing laws in Poland that would allow for revoking citizenship "acquired through naturalization."

The news came days after Nawrocki vetoed a bill that would have extended financial support for Ukrainians fleeing the war.