Lee Yuan-tseh, a Taiwan-born 1986 Nobel laureate in chemistry, has urged Taiwan's leader Chen Shui-bian to consider stepping down in an open letter issued on Thursday evening.

In the letter, Lee, a former advisor to Chen, said it was necessary for Chen to "seriously consider the issue of his continued leadership" as Taiwanese society is being rocked by the corruption allegations surrounding him and his family, and the indictment of his wife.

Last Friday, Chen's wife Wu Shu-chen was indicted by prosecutors for the alleged embezzlement of 14.8 million Taiwan dollars (450,000 U.S. dollars) in secret funds in the past five years.

It is widely believed that Lee played a key role in getting Chen elected to his first and second term in 2000 and 2004.

Chen did not respond publicly to Lee's letter, but asked his staff to express his gratitude to Lee, saying that he would listen to suggestions on various topics.

Ma Ying-jeou, chairman of the Kuomintang (KMT), said although Lee's statement had come a bit late, he thought it was a positive step.

Source: Xinhua