Areas of the Brands Hatch Grand Prix circuit will no longer be accessible to spectators after changes are made this season to improve spectator protection.
Some parts of the GP loop, which have yet to be specified, will be out-of-bounds to the public and others will have catch fencing erected.
It is not yet clear how much of the GP loop will be inaccessible to spectators, while the Indy circuit will not be affected.
The changes are part of a safety review by Brands owner MotorSport Vision that has "coincided with discussions" over the return of the DTM, which will race on the GP circuit for the first time this season.
An MSV statement read: "The changes to spectator access within the Grand Prix loop coincided with discussions with [DTM promoter] ITR about the return of DTM to Brands Hatch, but are primarily part of an ongoing review of spectator protection.
"The changes do not involve debris fencing being erected around the whole loop; instead they involve certain areas being designated as viewing areas, some without debris fencing, some with where required, and other areas designated as not for public access.
"This set-up will operate for all race events on the Grand Prix circuit and is not particular to DTM.
"The works to the inside of the GP loop will be finished in advance of the first race event on the Grand Prix circuit in May.
"Updated maps of spectator routes and viewing locations will be published in due course to clarify the changes."
Similar changes were discussed as recently as 2010, when a car driven by Francisco Carvalho vaulted the barriers in a SEAT Leon Eurocup race on the GP loop in July.
The rolling car narrowly missed a group of marshals.