Gretta Duisenberg-Nieuwenhuizen is a Dutch pro-Palestinian political activist. She is the widow of Dutch Labour Party (PvdA) politician Wim Duisenberg who was also the first president of the European Central Bank (ECB).
Duisenberg was born as Greetje Nieuwenhuizen into a strict Protestant family in Heerenveen, Friesland. She later studied nursing. Her first marriage was to the internist Bedier de Prairie, with whom she had three children. At that time she also started using the name Gretta. After their divorce, she became active in left-wing politics, human rights causes, and was briefly involved with Hans van Mierlo, at that time the Dutch Minister of Defense. She married Wim Duisenberg when he was president of De Nederlandsche Bank, the Dutch central bank.
Gretta Duisenberg came to international attention in 2002 when the media reported that the president of the ECB had a Palestinian flag hanging from his house in Amsterdam.
Gretta Duisenberg came under fire when she announced her intention of collecting six million signatures as part of her campaign to draw attention to the Israeli occupation of the Palestinian Territories. She was asked how many signatures she'd been able to gather for the petition against the occupation and replied that 6,000 supporters had signed so far. And how many signatures would you like to collect, she was asked. Duisenberg hesitated for a moment and then said, "Six million". Critics stated that the figure was clearly an allusion to the number of Jewish victims of World War II. Duisenberg denied any link to the Holocaust, and stated that she just mentioned a multiple of the 6,000 they had already collected.