Kallas, 47, is well-known for her tough stance on Russia and as a fierce critic of what she says are Russia’s expansionist aims.
She has led the Estonian government since 2021 and fronted the liberal Estonian Reform Party (Eesti Reformierakond) during the 2019 and 2023 general elections that the party won.
Until a new government is confirmed next month, Kallas will remain the Baltic country’s caretaker premier, Estonian public broadcaster ERR reported.
Observers consider her an uncompromising voice in the EU and NATO for unconditional support for Kyiv and in favor of containing Moscow.
Born in Estonia’s capital, Tallinn, Kallas is the great-granddaughter of the first Estonian police chief, who was appointed as the newly independent country emerged from the Russian empire after World War I, only to be absorbed into the Soviet Union in 1940.
During Kallas’s rule, Estonia became one of the highest per-capita military donors to Ukraine, following the invasion of that country by neighboring Russia in February 2022.
Her party plans to elect a new
leader on September 8.
Kristen Michal, the climate minister, is expected to become the next premier, “pending negotiations to reconfigure the cabinet with coalition partners,” the liberal Estonia 200 and the Social Democratic parties, Kallas’s Estonian Reform Party said.