The Dutch Crown Princess has been forced to move out of university accommodation out of fears she could be kidnapped by organised gangs.
Princess Catharina-Amalia, who is the heir to the Dutch throne, is under heightened security due to concern that she could be targeted by criminals.
"She can hardly leave the house," Queen Maxima said during a state visit to Sweden with her husband King Willem-Alexander.
Amalia started studying at the University of Amsterdam last month and had moved into an apartment in Amsterdam, but the royal couple now said concerns for her safety have forced her to move back to Huis ten Bosch royal palace in The Hague.
Last month, several Dutch media outlets reported that the princess, whose formal title is Princess of Orange, was under heightened security due to fears that criminal gangs may target her for kidnapping or an attack.
Dutch police and the country's secret service have declined to discuss security arrangements around the Royal House.
Dutch Prime Minister Mark Rutte on Thursday evening said he could not specify the details of the threats.
Princess Amalia started her politics and economics degree last month and was living in rented accommodation she shared with several other students in Amsterdam before she has had to move back home.
"This is terrible news, for her in the first place," Rutte told reporters. "Everyone involved is doing everything possible to make sure she is safe."
"The consequences are very difficult for her," ANP quoted Maxima as saying. "There is no student life for her like others have."
Amalia's lifestyle gained attention in December last year when her monarch dad was forced to apologise for hosting a party for his princess daughter during Covid.
Dutch royals celebrated Princess Amalia's milestone 18th birthday on Saturday with a glitzy garden party at a park near the palace.
A letter sent from Prime Minister Mark Rutte to other lawmakers said 21 guests attended the do.
Like many nations, the Netherlands is preparing for a wave of Omicron cases to overwhelm the healthcare system in the coming weeks.
The current Covid threat in the country is "level three", meaning the Dutch health service is facing "serious" pressure
In response, people are being asked to have no more than four visitors aged 13 or over in their home per day, CNN reports.
In the correspondence, Rutte said the princess's dad King Willem-Alexander admitted it wasn't appropriate to go ahead with the party.
The letter read: "The king informed me that on closer inspection it was not right to organise this.
"I think that's a sensible response."
According to Rutte, all guests were vaccinated, tested and adhered to social distancing measures. The park is also considered an extension of the royal family's home.
Previous celebrations for the princess's birthday had to be cancelled due to Covid and the weekend soiree was organised "last minute", Rutte adds.