He said that Mr. Sano had agreed to withdraw his design, and that a competition would be held to choose a new logo. In a statement issued late Tuesday, Mr. Sano again denied that he had copied or plagiarized the work of others to make the design.

The logo, which has been used in commercials and other promotional materials, was introduced on July 24. Last month, a Belgian graphic designer, Olivier Debie, sued the International Olympic Committee to prevent the logo’s use, saying that it closely resembled one he had created for a theater in Liège, Belgium, in 2011.

The organizers of the Tokyo Games defended Mr. Sano. But further accusations emerged. An earlier version of Mr. Sano’s logo was said to have resembled a poster from a 2013 exhibition in Tokyo; Mr. Sano acknowledged attending that event, but he said he did not remember the poster, according to Mr. Muto.

This week, Mr. Sano was accused of taking images from the Internet without permission to create backgrounds for the logo in some presentations. At the news conference, Mr. Muto said Mr. Sano had admitted doing that, but said he had meant for those images to be seen only by the selection committee. In his statement on Tuesday, Mr. Sano apologized to the other artists involved.