Prime Minister Jacinda Ardern's 'edible briefcase' birthday cake

Prime Minister Jacinda Ardern takes a briefcase packed with documents home each night, but this morning she was surprised with an edible version.

Ardern received a birthday cake decorated to look like a briefcase after celebrating her 40th birthday yesterday.

The PM shared a snap of the "briefcake" on her Instagram page.

"It seems entirely appropriate that this was the amazing cake the office blew me away with this morning," she wrote.

"Every night they send me off with one of these briefcases, an edible one made for a very nice change!

Jacinda Ardern was surprised with an edible briefcase for her 40th birthday. Photo / Supplied

"Thanks team, very grateful to work with such an amazing group of people."

Ardern has tried her hand at a few creative cakes of her own in the past, creating both a piano cake and a bunny cake for her daughter Neve.

Her partner Clarke Gayford also took to Instagram yesterday to share a birthday tribute to his "favourite achiever".

View this post on Instagram

I don't really do these posts, but I think a bit of symmetry like the number 40 is worth positing on. Happy Birthday today to my favourite achiever in the whole wide world, someone, who despite everything on her plate, still finds time to squeeze lots of fun, love and happiness into our wee family unit. The. Best. xx

A post shared by Clarke Gayford (@clarkegayford) on Jul 26, 2020 at 1:00am PDT