Finland's Sanna Marin, 34, was officially appointed as the country's prime minister on Tuesday, becoming the world's youngest sitting head of government.

The former transport minister takes the helm of a coalition of five parties that will all be led by women, once the prime minister takes over as head of her Social Democratic party next year. All but one of the female coalition leaders are aged under 35.

Marin became Finland's third female prime minister after her nomination was passed in parliament by 99 votes to 70 Tuesday and President Sauli Niinisto officially appointed the new centre-left cabinet.

She succeeds Antti Rinne, who resigned last week after losing the trust of one of his coalition parties over his handling of a postal strike.

Marin has made global headlines for becoming not only Finland's youngest ever leader, but also the world's youngest sitting head of government, ahead of Ukraine's Prime Minister Oleksiy Honcharuk who is currently 35.

But on Tuesday, Marin deflected questions about the international attention she has received over becoming the world's youngest premier. "My own thoughts have been on practical things and this week, I haven't followed what the press have been writing very much either at home or abroad," she told reporters outside parliament. Earlier this week she said: "I have never thought about my age or gender, I think of the reasons I got into politics and those things for which we have won the trust of the electorate." Marin grew up looked after by her mother and her mother's girlfriend, and said that her "rainbow family" showed her the importance of "equality, fairness and human rights".