Revd Hassan Abduraheem and Rev Kuwa Shamal (pictured above) have been charged with other offences including espionage after Revd Hassan helped pay for the treatment of a Darfur man injured at a political demonstration.
Speaking earlier this month about the pair and a third man - Abdulmonem Abdumawla - who stands charged alongside them, Chief Executive of the anti-persecution charity Christian Solidarity Worldwide (CSW), Mervyn Thomas said: "We are deeply concerned to learn of the serious charges levelled against Reverend Hassan Abduraheem and Abdulmonem Abdumawla simply for seeking to assist with medical expenses, and against Reverend Kuwa Shamal merely for being a Christian and a friend of Reverend Abduraheem."
Revd Hassan and Mr Abdumawla came to the aid of Ali Omer who was severely burned at Quran Karim University last year in an incident which what appears to reflect how government and intelligence forces are increasingly targeting Darfuri students and suppressing peaceful demonstration.
The crackdown follows the death of a senior member of the student wing of the ruling National Congress Party (NCP) when 150 NCP students violently attacked Darfuri students who were holding a meeting at the Sharg El Nil College in Khartoum.
Mervyn Thomas added: "These innocent men now face the possibility of a death sentence on evidence that would not justify an arrest, let alone a conviction, given its paucity.
"We call on the Sudanese Government to ensure that this trial is conducted with respect to Fair Trial Principles, which include regular access to legal representatives and family members.
"We also urge the government to end the harassment and targeting of Darfuri students and Christians by NISS and to uphold the rights of every Sudanese citizen, regardless of their religion or ethnicity."
The case against Reverends Abduraheem and Shamal and Mr Abdummawla comes at a time when severe restrictions are being applied against Christians by the government though the National Intelligence and Security Services, CSW says.