Controversy is rising in France over the return of ancient Korean books to South Korea.

The French daily “Libération” said Monday that some 170 curators have expressed their support for the protest lodged last week by the librarians of the National Library of France over the books’ return. The library is the current holder of the books.

Jacques Sallois, who served as the director of French national museums in 1993 when then French President François Mitterrand promised to return the books, expressed regret over the decision to return the books, saying that he believes the decision was made with commercial purposes in mind.

Meanwhile, former Culture Minister Jack Lang supported his country's decision to return the books, saying that France had made an unprecedented decision to return a part of Korean history.

The disputes come as South Korean and French officials are set to discuss from this week details on how to transfer 296 royal Korean books to Seoul.