The court heard from an officer of the National Intelligence and Security Service (NISS) in Sudan in the case of Revd Yat Michael and Revd Peter Reith.
The pastors have been charged jointly with acts of criminal conspiracy, undermining the constitutional system, espionage, disclosure and receipt of official information or documents, promoting hatred amongst sects, breach of public peace and offences relating to insulting religious beliefs.
Two of these charges carry the death penalty or life imprisonment if a guilty verdict is found.
A Christian anti-persecution charity Christian Solidarity Worldwide (CSW) said both men remain in a high security prison in Sudan but are no longer being chained up or being kept in solitary confinement.
Neither man is allowed visitors, according to CSW.
It has reported that they can only meet with their families and legal team when attending hearings.
The trial judge has set the next hearing for July, the pastors will face questioning and a decision will be made regarding which charges.
CSW says this case is the latest in a campaign of harassment against Christians in Sudan.
Mervyn Thomas, Chief Executive of CSW, said, "We continue to call for the immediate and unconditional release of Revd Yat Michael and Revd Peter Reith and the revocation of the extreme and unwarranted charges against them.
"We urge the prison authorities to allow regular family and lawyer visits.
"The denial of these visits is in violation of the principles of fair trial articulated in Article 14 of the International Covenant on Civil and Political Rights, to which Sudan is a party.
"The international community must hold Sudan to its obligations to protect and promote freedom of religion or belief and to ensure the right to a fair trial."
