At a press conference on Thursday for the Nobel Peace Concert, Johansson praised 2008 Nobel winner and former Finnish president Martti Ahtisaari for promoting peace on three continents over the past 30 years.
"It is important to remind young people that peace is the only real victory," said the actress, 24.
Johansson and Michael Caine will cohost the concert honoring Ahtisaari on Thursday night. The event, to be broadcast in more than 100 countries, will feature performances by artists including Diana Ross, Feist and Dierks Bentley.
'Deserving, Smarty Pants'The actress also stressed that mediation should be used to resolve conflicts instead of war, "not the way the U.S. has handled it the past two terms which is: 'Don't discuss.' "
Describing the Nobel Peace Prize, Johansson said, "I guess we think it is awarded to deserving, smarty pants. What's wonderful about the concert … is really to make this peace prize sort of more accessible."
A friend of the actress told PEOPLE about her involvement: "Scarlett was honored to be asked to asked to cohost the Nobel Peace Prize Concert in Norway. She wanted to do something important to show young people around the world that peace is attainable and within our reach."