About 80 percent of Reader's Digest Association Inc's senior secured lenders have agreed in principle to the magazine publisher's restructuring plan, a source familiar with the matter said on Thursday.

The media company, known worldwide for its family magazine, said on Monday it planned to file for Chapter 11 bankruptcy protection for its U.S. businesses as part of a prearranged plan with lenders to cut debt 75 percent to $550 million from the current $2.2 billion.