(Corrects to show Paramount sale would require unanimous approval)
NEW YORK, June 6 (Reuters) - Sumner Redstone's National Amusements Inc said on Monday that it had amended Viacom Inc's bylaws to require unanimous approval by Viacom's board for any deal related to Paramount Pictures.
The change, which is effective immediately, was made "to protect long-term interests of stockholders," National Amusements said in a news release.
National Amusements is the owner of 80 percent of Viacom's voting stock.
Reporting by Anna Driver; Editing by Bernard Orr