Hand in hand with his wife, the former prime minister of the Netherlands, died by euthanasia.
Both passed away at the age of 93. The news was made public on Friday by the Rights Forum, which said the couple died on Monday and will be buried in a private ceremony in the eastern city of Nijmegen.
"He died hand in hand with his beloved wife Eugenie van Agt-Krekelberg, with whom he stayed for more than 70 years," the statement said.
The couple had been in poor health for a long time. In 2019, Van Agt suffered a brain hemorrhage while giving a speech at a Palestinian memorial event and never fully recovered.

Van Agt led the Dutch government from 1977 to 1982.
The Christian Democrat left his party in 2017 over ideological differences with the centre-right's approach to Israel and the Palestinians.
Dutch Prime Minister Mark Rutte described Van Agt as his "great-great-grandfather in office".
"With his unique language, clear convictions and wonderful presentation, Dries van Agt gave color and substance to Dutch politics at a time of polarization and party renewal," Rutte said in a statement.
"He took administrative responsibility at a turbulent time and managed to inspire many with his wonderful personality and colorful style," King Willem-Alexander, Queen Maxima and Princess Beatrix said in a joint statement.
Van Agt was known for his grandiose language and passion for cycling. He was forced to quit this hobby in 2019 after he crashed.