"They must be courageous," Gorbachev told ABC7 through an interpreter.
Gorbachev also shared his view on the future of the North America Treaty Alliance.
"They should consider actually abandoning the whole project, not immediately liquidating NATO but gradually," said Gorbachev.
When he left office in 1992, Gorbachev said there were discussions about disbanding NATO with the end of the Cold War. He hopes NATO leaders will find more peaceful means to insure security.
"It is an illusion things can be done this way," said Gorbachev. "I think we should move toward different forms of cooperations including security."
Gorbachev expressed interest Tuesday in how his comments were reported the previous day.
Some of the other Nobel Peace prize winners have voiced their concerns about NATO and American military action during the summit. On Tuesday, they urged students in attendance and those watching coverage to make their concerns known.
As a child, Jody Williams stood up to bullies who taunted her hearing impaired brother. As an adult, she won the Nobel Peace Prize for her work to ban landmines.
"If you do not choose to exercise your rights and your power to stand up for what you believe in, you are giving your power away to those who will stand up," she said.
One discussion at the Nobel world summit Tuesday focused on women forging peace.
Caryl Stern is the president and CEO of the U.S. fund for UNICEF, which was awarded a Nobel Peace prize in 1965. She recalled having to navigate tricky political terrain in order to improve the quality of life for children in 157 countries.
"Attempt to be respectfully appropriate and at the same time push the envelope, because if we don't push it not will change," said Stern. "I am the child of a Holocaust survivor. I know what it means when no one stand up for anyone."
The world summit concludes Wednesday.
The Dalai Lama will attend the summit's last panel discussion, and Sean Penn will receive an award for his humanitarian work in Haiti.