Arsenal will sell players who enter the last two years on their contracts.
In recent seasons, Aaron Ramsey, Alexis Sanchez, Danny Welbeck and Jack Wilshere have all walked away from the Emirates without the club receiving a transfer fee.
The comments come from Gunners managing director Vinai Venkatesham, who told the club's website: "When we are selling players we need to maximise the funds we get to reinvest in the team.
"We need to be really disciplined when we are dealing with senior players who are not towards the end of their careers.
"So that means we have to start making the difficult decisions when they have two years left on the contracts.
"We're either going to renew those contracts or we're going to be selling them.
"We're going to have to be brave in those decisions because we can't be in a situation where we're allowing players to walk out of the door for free unless they are coming towards the end of their careers."