U.N. rights experts and Britain are speaking out against Sudanese court order to hang a pregnant Christian woman for marrying a Christian man and refusing to renounce her faith.

Meriam Yahia Ibrahim Ishag, a 27-year-old who is eight months pregnant with her second child, was sentenced to 100 lashes and death by hanging this Mother's Day under the Islamic sharia law that has been in force in Sudan since 1983 and makes conversions of faith punishable by death.

"This outrageous conviction must be overturned and Ms. Ibrahim must be immediately released," insisted the U.N. experts on a range of issues, including the human rights situation in Sudan, violence against women, minorities and the freedom of religion or belief.

They stressed in a statement that under international law, "the death penalty may only be imposed for the most serious crimes, if at all," AFP reported.

"Choosing and/or changing one's religion is not a crime at all. On the contrary, it is a basic human right," the experts said.

The young mother was found guilty of apostasy, or publicly renouncing Islam. Sudanese law considers Ibrahim a Muslim due to her father's religion; however, she was raised by her Ethiopian Christian mother after her father left them.

"I was never a Muslim. I was raised a Christian from the start," she told the court.

Under Sudan's interpretation of sharia, a Muslim woman cannot marry a non-Muslim man and any such relationship is regarded as adulterous.

Ibrahim's husband, Daniel Wani, is a Christian. He said in an interview with VOA last week that police prevented him from attending his wife's final appeal but that he will continue to fight for her life. ""I'm so frustrated. I don't know what to do. I'm just praying," he stated.

The U.N. experts said that the right to marry and found a family was a fundamental human right, and voiced particular concern that Ibrahim was being held with her 20-month-old son in "harsh conditions" at the Omdurman's Women Prison near Khartoum.

"The imposition and enforcement of the death penalty on pregnant women or recent mothers is inherently cruel and leads to a violation of the absolute prohibition of torture and other cruel, inhuman or degrading treatment or punishment," they warned.

The U.N. experts called on Sudan to repeal all discriminatory laws, adding there was a "pressing need to address the pattern of discrimination, abuse and torture as well as the subjugation and denigration of women in the country."

Western embassies and Sudanese activists sharply condemned the accusations and called on the Sudanese Islamist-led government to respect freedom of faith.

'The details of this case expose the regime's blatant interference in the personal life of Sudanese citizens,' Sudan Change Now Movement, a youth group, said in a statement.

In the United States, the White House released a statement strongly condemning the sentence and urging the Government of Sudan to meet its obligations under international human rights law.

A petition has been created on Change.com calling for Ibrahim's release. "Religious freedom should be a human right. I was raised as a Muslim and I find this atrocious and embarrassing," wrote one signer named Zaid Kharrat.

If the death sentence is carried out, Ibrahim will be the first person executed for apostasy under the 1991 penal code, Christian Solidarity Worldwide, a British-based campaign group, said last week.