Science magazine will not retract cloning pioneer Hwang Woo-suk's thesis on stem cell research despite the escalating controversy on how he obtained human eggs for experiments.

The Washington Post on Tuesday quoted Science editor-in-chief Donald Kennedy as saying the magazine has no data suggesting Hwang's science is invalid, but will run a correction if the published disclaimer about egg payments was false.

The daily in an article described details of the rising controversy and the admission by the head of a fertility clinic that he paid for the eggs used in Hwang's research.