Prince Harald von Hohenzollern has died from a heart attack while on a work trip just days before the birth of his first child.

The German royal, 63, was in Namibia on the southeast coast of Africa, to explore diamond mines, when tragedy struck.

Hohenzollern wed Josefa von Hohenzollern just nine months ago.

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Josefa, who is heavily pregnant, is also running for re-election as mayor in the town of Leonberg, Germany. She shared the news of his death on social media.

“Dear fellow citizens of Leonberg, today I am writing with a heavy heart,” she began on Instagram.

German prince Harald von Hohenzollern has died on a work trip just days before the birth of his first child, his wife, Josefa, has announced. Credit: Instagram

“My beloved husband Harald v. Hohenzollern died quite unexpectedly of a sudden cardiac death. This loss hits me very deep.

“I need time to grieve, say goodbye and be there for our unborn child. That’s why I will be stepping back from campaigning and social media in the coming days.

“I hope for your understanding during this time off and thank you from the bottom of my heart at this point for your condolences and support.”

Josefa said she would continue with her candidacy.

The Hohenzollern house is a famous German dynasty which dates back to 1061.

Despite the impressive lineage, Harald and Josefa had a very modern love story.

The couple met at a trade fair before tying-the-knot in Kollnburg last September.

The princess was quickly flooded with support from followers.

“My deepest sympathy, I don’t find the right words. I pray for you and your unborn child. Wishing you love, strength and comfort,” one person wrote.

“Sincere condolences and much strength,” another added.

“Our sincere condolences to you and your family during these difficult hours,” another wrote.