The London-based journal Science says it will retract Hwang Woo-suk's research paper if the authors do not promptly follow the proper procedures.

In a news release Friday, Science said it will post an editorial retraction if Hwang's research team or an investigative panel of Seoul National University fail to respond by the December 30th deadline.

The panel on Friday dropped the bombshell announcement that the cloning scientist had lied about creating stem cell lines.

Hwang and his former American collaborator Gerald Schatten have asked Science to retract their paper published in May, but the journal requires the written consent of all co-authors.