A Sudanese woman facing death for refusing to renounce Christianity after allegedly converting from Islam has appealed against the sentence, her lawyer said.

The appeal demands the release of Mariam Ibrahim, and says the court that tried her committed procedural errors, her lawyer, Eman Abdul-Rahim, told the AP news agency late on Wednesday.

Ibrahim, 27, was sentenced to death for "apostasy" last month by a Khartoum court for allegedly converting to Christianity from Islam. She maintains that her Muslim father left when she was young and that she was raised a Christian by her Ethiopian mother, who is an Orthodox Christian.

Ibrahim married a Christian man from southern Sudan in a church ceremony in 2011 [Al Jazeera]

Ibrahim married Daniel Wani, a Christian from southern Sudan who has US citizenship, in a church ceremony in 2011. Muslim women in Sudan are prohibited from marrying non-Muslims, though Muslim men can marry outside their faith.

Ibrahim has an 18-month-old son, Martin, who is living with her in jail. She gave birth to a second child last week. By law, children must follow their father's religion.

A video obtained by AP shows Ibrahim with her newborn and her son Martin at the prison's hospital where she gave birth. Looking happy and relaxed, the video shows Ibrahim breastfeeding the baby while seated on a bed with Martin sitting close by.

The rights group Amnesty International condemned the sentence against Ibrahim, calling it abhorrent, while the US State Department said it was "deeply disturbed" by the sentence.

Sudan introduced Islamic law in the early 1980s under the rule of Jaafar Nimeiri, a move that contributed to the resumption of a rebellion in the mostly animist and Christian south of Sudan.

Source: Associated Press