Cloning pioneer Hwang Woo-seok wants to hold talks with religious leaders to seek their understanding of his research.

The Seoul National University professor is in the United States attending the Stem Cell Policy and Advocacy Summit in Houston, Texas.

Saying he respects concern raised by Seoul Archbishop Cheong Jin-suk, Hwang promised to seriously consider the opinions of religious leaders and civic groups in carrying out his research.

Earlier, Cheong warned that Hwang's work has serious repercussions because it hurts life even with the intent of fighting incurable diseases.

Hwang, however, denied that his research is unethical since stem cells have no chance of becoming human nor does it call for any killing.

Also attending a similar conference in Brazil earlier this week, he also pointed to active research in stem cells in predominantly Catholic countries like Brazil and Spain.