The United State's House of Representatives last night approved bipartisan legislation that would permit more federal funding of stem cell research on human embryos that would otherwise be discarded.
The legislation was easliy passed, despite a veto threat from US President George W. Bush.
The House also approved by a 431-1 vote less controversial legislation that would expand research involving cells drawn from umbilical cord blood.
The embryonic stem bill would allow federal funding of stem cell research involving excess embryos from in vitro fertilization that would otherwise be discarded. It would not allow cloning a human baby.
The bill passed with a comfortable 238-194 margin, but was well short of the two-thirds threshold needed to override Mr Bush's threatened veto. Opponents of embryonic stem cell research believe it destroys human life and object to using taxpayer dollars to finance it.
Stem cells have the ability to transform themselves into many other types of cells, offering the potential for regenerating damaged organs or tissue.
After the House vote three Democratic and three Republican senators wrote to Senate Majority Leader Bill Frist asking for swift Senate action on the legislation.