Story highlights Queen Beatrix will abdicate Tuesday after 33 years as the Dutch monarch

Willem-Alexander will be first king the Dutch have had in more than 120 years

The 75-year-old monarch announced her abdication in January

New queen's father, a former Argentinian minister, will miss investiture

A chapter was closing in Dutch history Monday as Queen Beatrix spent her last full day on the throne after 33 years as the country's monarch.

Beatrix will abdicate on Tuesday morning, handing over to her eldest son, Willem-Alexander, who will be the first Dutch king in more than 120 years. The queen was due to give a televised speech later on Monday.

She steps down on the national holiday known as Queen's Day, an opportunity for people across the Netherlands to dress up and party. The investiture of the new king will be the high point of a year of celebrations marking the end of the Napoleonic occupation in 1813.

"Until today, this beautiful task has given me a lot of satisfaction. It is inspiring to feel close to people, to sympathize in grievances and share times of joy and national pride."

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She went on: "It is with great confidence, that on April 30 this year I will pass my kingship to my son, the Prince of Orange. He and Princess Maxima are fully prepared for their future task. They will serve our country with devotion, faithfully serve the constitution, and with all their talents give substance to their kingship."

Dutch Prime Minister Mark Rutte added: "Anyone who has met the queen will agree that she touched people and helped them forward with her knowledge and experience and her great interest and involvement."

The Dutch media has speculated that the queen was abdicating to spend more time with her second son Friso, who was injured in an avalanche at an Austrian ski resort last year. He remains in a coma in a London hospital.

Prince Willem-Alexander was educated in Wales and Holland, where he earned a history degree at Leiden University. He served in the Dutch Royal Navy from 1985 to 1987. As Prince of Orange -- the title given to the person first in line to the Dutch throne -- he has been interested in sustainability and innovation.

He is married to Princess Máxima, who was born in Buenos Aires, Argentina. She has a degree in economics and has worked for HSBC and Deutsche Bank. The couple have been married for 11 years and have three daughters.

Last week the couple gave their first joint TV interview in which Willem set out how he intended to rule. "I want to be a king who is first of all traditional, built on the tradition of my predecessors, who stands for continuity and also for stability in the country ... but also a king who in the 21st century can bind together and represent society as a whole."

Asked how he intended to do that, Willem told the NOS state broadcaster: "By being present where you think people need support or help, by giving extra attention and presence to worthwhile events and by supporting people who are in need."

One notable absence at Tuesday's ceremony will be the new queen's father, Jorge Zorreguieta, who was a minister during the 1976-1983 Argentinian military dictatorship.

Princess Maxima said her family would not attend her swearing-in as queen because of her father's controversial past.

"This is a constitutional event, when my husband becomes king and my father doesn't belong there, especially if there are issues," the princess told NOS. "He remains my father, we still enjoy our private moments."

Mark Saunders, a royal biographer, said he had bumped into the new king and found him to be personable and relaxed. "I met him in the strangest of circumstances," he said. "I was on a ferry stuck between Estonia and Norway. I spoke to this young pleasant guy who gave me some advice that maybe you should get off (the boat). It was only afterwards that I discovered it was Crown Prince Willem. I remember thinking that this was the most 'non-royal' royal I've ever met. I haven't met that many, but he was a pleasant guy.

"He's young too, only 46 -- so he's the youngest monarch in the world -- the only one who's not gray or bald!"

Saunders said he believed that in contrast to Beatrix, Britain's Queen Elizabeth would never abdicate, because of the 1,000 years of history behind her, and the trauma of her uncle, King Edward VIII's abdication. "(Britain's royals) believe they have a divine right to rule, which goes back to the Norman Conquest of 1066. They will never break that chain," he said.