(CNSNews.com) - Both sides in the human embryo cloning debate turned up the volume of their rhetoric Tuesday in anticipation of a Senate vote on the issue later this month or in April.

Christopher Reeve, the actor who once played Superman, but was later paralyzed below the neck in an equestrian accident, warned that if the government refuses to fund and provide oversight for embryonic cloning, "it will happen privately, dangerously unregulated and controlled."

Supporters of so-called therapeutic cloning argue it has the potential for producing stem cells that could yield major scientific breakthroughs in curing human diseases. Opponents contend it's unethical to create human embryos either for reproductive purposes or for the purpose of destroying them for research.

Senate Majority Leader Thomas Daschle (D-S.D.) promised Sen. Sam Brownback (R-Kan.), a leading opponent of embryonic cloning, that Senate debate on the issue would begin in February or March. But with only 13 days left on the legislative calendar in March, it may be delayed until April.

Tuesday, Reeve joined supporters of embryonic cloning in testifying before a Senate panel chaired by Sen. Ted Kennedy of Massachusetts. Reeve said the extraction of stem cells from cloned human embryos would not lead to embryo farms, as opponents have warned.

"That's nonsense, because we will be able to regulate what happens," Reeve said at a news conference prior to the hearing.

Because so-called therapeutic cloning does not require fertilization of an egg, like normal human reproduction, it is not a process that destroys human life, Reeve said.

"If we don't make this research legal, if we don't use government funding and oversight, it will happen privately, dangerously unregulated and controlled," Reeve said, adding that the U.S. would "lose its preeminence in science and medicine."

Brownback and Democratic Sen. Mary Landrieu of Louisiana have introduced a bill to ban embryonic cloning. During a separate news conference, Landrieu warned that human cloning will "[turn] the miracle of birth into a manufacturing process" and lead to the exploitation of women who will be tempted to sell their eggs for money.

The "human body is not a product to be mass produced and stripped in parts," said Landrieu, who also testified at the hearing chaired by Kennedy.

Landrieu and Brownback stressed that their bill does not preclude other types of research, including embryonic stem cell research or the (non-embryonic) cloning of human tissues.

"Momentum is continuing to grow behind the bipartisan bill, which currently has 23 co-sponsors," said Brownback of the bill he and Landrieu are co-sponsoring (S. 1899). "A broad coalition of groups on the left, in the middle and on the right ... support a ban on human cloning."

Senators Tom Harkin (D-Iowa), Barbara Boxer (D-Calif.), Harry Reid (D-Nev.) and Arlen Specter (R-Pa.) have a competing bill, S. 1893, that would allow embryonic cloning but would impose criminal and civil penalties for anyone who tried to clone a human being for reproductive purposes.

The House passed a ban on human cloning last year.