Speaking in a new video for his Freedom Party (PVV), Wilders condemned the attacks in Cologne, Germany, in which hundreds of women were groped and robbed by a mob of mostly Arab and North African men.
He called the attacks "sexual terrorism, sexual jihad," and repeated calls for the Netherlands to close its borders to all "asylum-seekers from Islamic countries."
"But as long as this doesn't happen, as long as our women are in danger from the Islamic testosterone bombs, I propose that we lock the male asylum seekers up in the asylum centers," he said.
The Netherlands took in a record number of asylum-seekers last year, receiving more than 54,000 by the end of November.
— Geert Wilders (@geertwilderspvv) January 18, 2016
Wilders' views have already sparked controversy. He was charged with inciting racial hatred after making a campaign pledge to ensure there will be "fewer Moroccans" in the country.
His party, the PVV, is planning to hand out fake pepper spray to women at a political rally this weekend. Carrying pepper spray is illegal in the Netherlands, but Wilders has said it should be legalized.