Texas - The US President, Mr Bush, warned yesterday he would veto any attempt by Congress to expand federally funded embryonic stem-cell research beyond the plan he unveiled last week.
"The statement I laid out is what I think is right for America. And any piece of legislation that undermines what I think is right will be vetoed," Mr Bush said.
Mr Bush last week approved funding for stem-cell research limited to about 60 stem-cell lines believed in existence from embryos that were destroyed in the process. He opposed allowing stem cells to be extracted from some 100,000 embryos frozen in fertility clinics. Scientists say more stem cells will be needed.