HELSINKI - Finland's Sanna Marin is to become the world's youngest prime minister at the age of 34.

The transport minister was picked by her Social Democratic party after its leader, Antti Rinne, quit as PM. She will be sworn in this week.

She will lead a centre-left coalition with four other parties, all headed by women.

Mr Rinne stepped down after losing the confidence of a coalition member over his handling of a postal strike.

When she takes office, Ms Marin will be the world's youngest sitting prime minister. New Zealand PM Jacinda Ardern is 39, while Ukrainian premier Oleksiy Honcharuk is 35.

Media reports say Sanna Marin was raised in a "rainbow family", living in a rented apartment with her mother and her mother's female partner. She told the Menaiset website (in Finnish) in 2015 that as a child she felt "invisible" because she was unable to talk openly about her family.

But she said her mother had always been supportive and made her believe she could do anything she wanted.

She was the first person in her family to go to university.

Ms Marin rose quickly through the ranks of the Social Democrats, heading the city administration in Tampere at the age of 27 and becoming an MP in 2015.

She has been transport and communications minister since June and has a 22-month-old daughter.

There are unlikely to be any major policy changes, as the coalition agreed a programme when it took office.

However, Ms Marin, who won the vote for prime minister by a narrow margin, made it clear it would not be business as usual.

"We have a lot of work to do to rebuild trust," she told reporters.

She brushed away questions about her age, saying: "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."(FA)