Dmytro Kuleba resigned as Ukraine's top diplomat on Wednesday as President Volodymyr Zelenskyy starts to reshuffle his government. One analyst says it may be calculated to take advantage of domestic issues among Western allies.
Kuleba was popular in Ukraine and no reasons have been given for his departure.
But sources in Ukraine's presidential administration told AFP that he had been criticized for the functioning of his ministry and had been under pressure from Zelensky's chief of staff Andriy Yermak.
His deputy, Andriy Sybiga, a former ambassador to Turkey and ex-presidential office staffer, is rumored to be replacing him.
Other major changes are expected in the cabinet.
The moves come after Moscow targeted Ukrainian cities with devastating missile attacks.
A Russian strike on the historic center of Lviv in western Ukraine has killed seven people including three children, officials said Wednesday. It followed a Tuesday missile strike that killed more than 50 in Poltava.
Zelenskyy made the move now because he sensed a window of opportunity.
"The West can't criticize him now because they have a lot of domestic issues to deal with – the US election, election trouble in Germany and France," said Ukrainian political scientist Mykola Davydiukhe told CNN.
