Denmark's King Frederik X takes throne as Queen Margrethe abdicates

King Frederik X became Denmark's new regent on Sunday as his mother Queen Margrethe signed a declaration of her abdication.

Thousands of Danes flooded the streets between the palace and royal residence in the capital Copenhagen to witness the unprecedented event. The queen signed a declaration of her abdication at a government council at the parliament.

The signing ceremony officially designated Frederik to become king. Police in the city estimate that more than 100,000 people turned out in the streets to welcome the new King.

Born in 1968, Frederik Andre Henrik Christian is the first child of Margrethe and her late husband, Prince Henrik, who died in 2018. His forename was chosen in line with the Danish royal custom of the heir apparent being named either Frederik or Christian. His only sibling, Prince Joachim, was born in 1969.

King Frederik's son Christian — now officially crown prince — was also present at the signing ceremony. Meanwhile, Australian-born Mary is the first commoner to become queen in Denmark.

Copenhagen police predicts a turnout of more than 100,000 people in the streets to welcome the new King.

Queen Margrethe announced her intention to abdicate the throne in her New Year's Eve address. Aged 83, she said she would formally step down on Jan. 14 after five decades on the throne.

She ascended the throne in 1972, following the death of her father, King Frederik IX. She has become the first Danish monarch in nearly 900 years to abdicate voluntarily.