The renowned U.S. journal Science has defended stem cell studies by cloning pioneer Hwang Woo-suk, calling 'groundless' recent allegations impugning the validity of his work.

In an editor's statement, the publication said reporters began to inquire after different versions of charges apparently raised by a Korean TV station from the week of November 28th, but that none of the accusations were credible.

The weekly journal said it will avoid speculation until a specific, scientific claim against Hwang's research is reported.

Science pointed out that as of Thursday, no scientist, thesis publisher or expert who reviewed Hwang's paper has raised suspicions over his findings.

It stressed that Hwang's two stem cell studies submitted to the journal published last year and this year were thoroughly reviewed in a "flawless" process.

The journal also said that crew members from Korea's MBC-TV news magazine "Producer Notebook" came to interview its chief editor Donald Kennedy, but that the allegations they raised were mere hearsay.