More than 20 Iraqi Christians who have fled ISIS, crossing into the US from Mexico, have been denied religious asylum by the USA, and could be extradited within days.

Twenty-seven Iraqi Chaldean Christians have been held at the Otay Detention Centre in San Diego since entering the US in April and May.

The majority, 22 of the 27, have been ordered out of the US and five have asylum applications pending. Seven of these have already been extradited and five have been charged with making false statements, according to Lauren Mack, spokesperson for US immigration and Customs Enforcement in San Diego.

Mack said that the Chaldeans have not and will not be sent back to Iraq, but repatriated to "agreed upon" nations like Germany and Sweden.

The Chaldeans are being deported despite several of them having family in San Diego willing to take them in.

"This is extremely disturbing and wrong," Jim Jacobson, president of Christian Freedom International, told Fox News.

"Until this decision, having a family sponsor has always been a huge positive factor in adjudicating asylum cases," said Jacobson. "Christians are facing unspeakable torture and atrocities at the hands of ISIS."

Mack defended the decision, saying there are legal immigration protocols that need to be followed for family sponsorships, which were not adhered to by the Chaldeans.

There are also allegations that at least some of the Chaldeans have German passports, and are therefore not eligible for asylum under international law.

Jacobson said he is fearful of the implications the verdict will have for future Christian asylum seekers. It may "make it impossible for any Christian man, woman or child facing persecution because of their faith" to gain entry into the USA, he said.