A US federal judge denied Tuesday the White House's request to drop his decision to temporarily block federal funding for embryonic stem cell research pending an appeal of the decision.
"In this court's view, a stay would flout the will of Congress," Judge Royce Lamberth wrote in his order.
"Congress remains perfectly free to amend or revise the statute. This court is not free to do so."
Lamberth first issued his injunction on August 23, ruling in favor of a coalition that included several Christian organizations by saying that stem cell research involved the destruction of human embryos.
He said the federal funding, which President Barack Obama had authorized, violated the Dickey-Wicker amendment, a federal law barring federal tax funds from being used to fund any research that would cause human embryos to be destroyed.
That decision prompted the White House to say it would seek ways to keep the "life-saving" research going.
In Tuesday's order, Lamberth said the Obama administration was "incorrect about much of their 'parade of horribles' that will supposedly result from this Court's preliminary injunction."
Obama's March 2009 decision to reverse the ban on federal funds research on embryonic stem cells was lauded by many researchers who believe the field has huge potential for treating serious diseases including Alzheimer's, Parkinson's and diabetes.
It came after his predecessor George W. Bush had banned federal funding for research on new stem cells for moral and religious reasons.
The research is fiercely opposed by religious conservatives, who believe that life begins at conception, because it involves the disposal of embryos.
Researchers believe that stem cells, so-called because they are the foundation for all human cells, provide two promising avenues for scientists.
First, they can be used for research that cannot be performed inside the body. But scientists believe they can also coax the foundational cells into cardiac, pancreatic or brain cells to replace damaged or infected cells and allow tissue or organs to reconstitute themselves.