President Bush took the unusual step of a nationally televised address last night to announce his decision concerning federal funding for stem cell research, ending months of deliberations and intense lobbying from both sides on the controversial matter.
Mr Bush has delayed funding for months as he wrestled with the issue. He has conferred with experts on the scientific, ethical and religious implications of the research, and has insisted that political considerations were not part of his deliberations.
Still, Mr Bush recently met Pope John Paul II, who strongly urged him to oppose funding. Mr Bush has been aggressively courting Catholic voters in the US.
But a handful of conservative Republicans, such as Senator Orrin Hatch of Utah and Senator Strom Thurmond of South Carolina, have called for federal funding of the research because of the potential pay-off in treatment of a number of diseases.
In addition, the First Lady, Mrs Laura Bush, said in a recent CNN interview that embryonic stem cell research could save lives, and leftover embryos from fertility treatments are destroyed anyway.
Mrs Bush also made a point that has been noted by stem cell opponents - that researchers could simply use stem cells from adults, rather than from embryos.
"I mean, there is other research - other ways to get to the same kind of research," she said.
Asked about the unusual nature of the address - Mr Bush has not been keen on taking to the airwaves - the White House spokesman, Mr Ari Fleischer, said: '"The President wants to share the decision with the American people himself so they can see and hear why he came to the decision he came to. He wants to share this directly with the American people."
At issue is federal involvement in research on cells extracted from embryos that are left over from fertility treatments.
While supporters of such research see great potential for medical breakthroughs, opponents insist that it is wrong to use human embryos for research.
They point out that in order to remove the stem cell, the embryo must be destroyed.
Stem cells essentially are blank cells - capable of developing into any of the body's organs but not into a complete individual. These cells form inside an embryo a few days after fertilisation.
The National Institutes of Health is calling for federal funding of studies with embryonic stem cells that have been extracted by privately funded researchers. Mr Bush has delayed such funding while the policy is reviewed.
By properly nurturing embryonic stem cells, experts believe they will be able to grow new cells to restore ailing organs in chronically ill patients.
For instance, new insulin-producing cells could be grown to perhaps cure diabetes.