Estonia’s Prime Minister Kaja Kallas has stepped down as the leader of the Baltic country to become the foreign policy chief of the European Union later this year.

Ms Kallas, Estonia’s first female leader, handed in her formal resignation to President Alar Karis during a brief meeting at the Presidential Palace in the capital, Tallinn, on Monday.

Estonia under Ms Kallas has been one of Europe’s most vocal backers of Ukraine following the full-scale Russian invasion in February 2022.

Summing up Ms Kallas’ three and a half years at the helm of the nation of 1.3 million, Mr Karis was quoted as saying by the Baltic News Service that “it has been a time full of crises, the milestones (such as) the coronavirus, the economic recession and the war in Europe, when Russia destroyed our previous security picture with its aggression in Ukraine”.

The Prime Minister’s move automatically triggered the resignation of Ms Kallas’ three-party cabinet, made up of her centre-right Reform Party, the Social Democratic Party and the liberal Estonia 200 party.

It will continue as a caretaker government until the new cabinet has been sworn in, most likely at the end of July or early August.

The Reform Party announced on June 29 that it is chose party veteran and climate minister Kristen Michal to replace Ms Kallas, whose last main duty was to represent Estonia at a Nato summit in Washington last week.

Mr Michal’s nomination will have to be approved by Mr Karis and the 101-seat parliament, or Riigikogu, where the coalition holds a comfortable majority. He has been serving as the minister for climate affairs since April last year.

The 49-year-old former economics and justice minister has been active in the Reform Party, Estonia’s key political establishment, since the late 1990s.