Desmond Tutu, Kofi Annan and Bono attended a private ceremony on Saturday in memory of Dutch Prince Friso, who died in August after failing to recover from a skiing accident, local media reported.
The ceremony took place in the Oude Kerk church in Delft, where the prince in April 2004 married Mabel Wisse Smit in defiance of parliament, a union which cost him his claim to the throne.
Others among the 900 or so guests at the memorial included Prince Haakon of Norway and Mark Rutte, prime minister of the Netherlands.
The second son of former queen Beatrix, Friso died on August 12 aged 44 from injuries sustained in a skiing accident that occurred in Austria in 2012 when he was caught in an avalanche.
He was buried on August 16 at his mother's castle in the small village of Lage Vuursche, 30 kilometres (18 miles) southeast of Amsterdam.
Prince Friso was the first for several generations not to be buried at the Nieuwe Kerk (New Church) in Delft, where most members of the Dutch royal family are buried.
Dutch media have speculated that he no longer felt officially part of the Dutch Royal House because of the state's rejection of his wife.
His marriage was not authorised by the parliament, as it has to be according to the constitution, because his wife had hidden a previous relationship with a Dutch drug baron.
Earlier this year Beatrix announced her abdication in favour of her eldest son, Willem-Alexander.