The UK Daily Telegraph reports that under draft government legislation to be debated by Parliament later this year, scientists will be given permission for the first time to create such embryos for research as long as they destroy them within two weeks.
But the Catholic bishops of England and Wales, in a submission to the Parliamentary joint committee scrutinising the draft legislation, said that the genetic mothers of "chimeras" should be able to raise them as their own children if they wished.
The bishops said that they did not see why these "interspecies" embryos should be treated any differently than others.
The wide-ranging draft Human Tissue and Embryo Bill, which aims to overhaul the laws on fertility treatment, will include sections on test tube babies, embryo research and abortion.
Ministers say that the creation of animal-human embryos - created by injecting animal cells or DNA into human embryos or human cells into animal eggs - will be heavily regulated.
They insist that it will be against the law to implant "chimeras" - named after the mythical creature that was half man and half animal - into a woman's womb.
The bishops, who believe that life begins at conception, said that they opposed the creation of any embryo solely for research, but they were also anxious to limit the destruction of such life once it had been brought into existence.
In their submission to the committee, they said: "At the very least, embryos with a preponderance of human genes should be assumed to be embryonic human beings, and should be treated accordingly.
"In particular, it should not be a crime to transfer them, or other human embryos, to the body of the woman providing the ovum, in cases where a human ovum has been used to create them.
"Such a woman is the genetic mother, or partial mother, of the embryo; should she have a change of heart and wish to carry her child to term, she should not be prevented from doing so."
The Catholic bishops said that most of the procedures covered by the Bill "should not be licensed under any circumstances", principally on the grounds that they violate human rights.
Pope backs adult stem cell research
Meanwhile, ABC News reports that Pope Benedict XVI has endorsed adult stem cell research, distinguishing it from the manipulation of stem cells from human embryos, which the Church condemns.
Speaking at the end of his weekly general audience yesterday, the pope saluted delegates at a global conference on the use of adult stem cells to treat cardiac problems, organised by La Spaienza University in Rome.
"On this matter the position of the Church, supported by reason and by science, is clear," he said.
"Scientific research must be encouraged and promoted, so long as it does not harm other human beings, whose dignity is inviolable from the very first stages of existence."
Image: Patricia Piccinini, We are family
Chimera embryos have right to life, say bishops (Daily Telegraph, 27/6/07)
Hybrid embryos should be borne (Aftenpost, 27/6/07)
Pope backs adult stem cell research (ABC News, 28/6/07)
LINKS (not necessarily endorsed by Church Resources)
Definition of Chimera (MedicineNet)
Stem cells (Wikipedia)
We are family (Patricia Piccinini)
NSW stem cell law passes (CathNews, 27/6/07)
Bush vetoes US stem cell legislation (CathNews, 22/6/07)
Don't whinge over Church doctrine, NSW MP tells colleagues (CathNews, 21/6/07)
Don't privatise religion: Christian thinktank (CathNews, 19/6/07)
Pell slams "stalinist" parliamentary contempt probe (CathNews, 18/6/07)
WA speaker raps Hickey (CathNews, 15/6/07)
Pell sticks to stem cell guns (CathNews, 12/6/07)
WA parliament may reprimand Hickey (CathNews, 8/6/07)
Anglicans, Baptists back Pell (CathNews, 8/6/07)
Coast to coast controversy over stem cell vote (CathNews, 7/6/07)
Catholic pols defy stem cell communion threat (CathNews, 6/6/07)
Pell slams "open slather" for stem cell research (CathNews, 5/6/07)
Life office slams human "sub-class" Vic cloning law (CathNews, 11/5/07)
Hart confronts Bracks over cloning legislation (CathNews, 12/4/07)
Bracks defies Pope on cloning (CathNews, 19/3/07)
Archbishop Hart condemns cloning laws (CathNews, 14/3/07)
Christianity not driver in cloning vote: Garrett (CathNews, 19/12/06)
Christian opposition fails to stop cloning bill passage (CathNews, 7/12/06)
Late amendment puts cloning bill passage in doubt (CathNews, 6/12/06)
Premiers face stem cell backlash as Hart criticises debate (CathNews, 24/7/06)
Catholics divided over stem cells (CathNews, 14/7/06)
Don't lift ban on cloning, says Brennan (CathNews, 23/6/06)