Mikheil Saakashvili, the former Georgian president, has been stripped of his Ukrainian citizenship, Ukraine's migration service has said.
He accused President Poroshenko of Ukraine of crossing a red line.
Ex-Deputy Prosecutor General of Ukraine, Davit Sakvarelidze, a Saakashvili ally, wrote on Facebook that Ukrainian President Petro Poroshenko is running ahead of other dictators of the world. The ex-Georgian president, who is wanted at home, lashed out at Poroshenko's "oligarchic regime". He lost his Georgian citizenship in 2015 after becoming a Ukrainian national.
Known for sweeping pro-Western reforms in his native Georgia which he led from 2004 to 2013, Saakashvili was a strong supporter of Ukraine's Maidan uprising and as a reward Poroshenko appointed him as governor of Ukraine's Odessa region in 2015.
In the post of Odessa governor, Saakashvili clashed with local elites and made harsh statements, including to Poroshenko's administration, accusing the president's team of corruption.
Saakashvili's party, "Movement of New Forces" (MNF), called on Ukrainians to gather in central Kiev on Thursday to protest against the abuse of authority. His popularity declined in his later years in office, in part because of a five-day war with Russian Federation during which Moscow's forces drove deep into the South Caucasus country, and his long-ruling party was voted out of power in a 2012 parliamentary election.
It did not provide the exact reason, but stated that this could be done if a Ukrainian national acquired citizenship of another country or submitted false documents.
"Their secret meeting lasted more than two hours and was nearly entirely devoted to me", Saakashvili claimed.
Saakashvili dismissed that explanation, saying that no country including Ukraine has officially accepted the charges filed against him in Tbilisi.
"Saakashvili will be forced to seek refuge in America and forget about American politics", Leshchenko said.