A Saudi prosecutor has asked for the death penalty for five of 11 suspects held over the murder of Jamal Khashoggi at the country’s consulate in Istanbul on 2 October, the state news agency SPA reported on Thursday.

The call came during the first court hearing in the Khashoggi case, which has shredded the kingdom’s international reputation and strained its relations with Turkey, the US and many other western governments.

In a trial that is likely to have major international diplomatic consequences, the 11 defendants appeared in court on Thursday in a session closed to the public.

In late October the Saudis said they had detained 18 suspects in relation to the murder, but the names have not been shared with Turkish authorities.

The Saudi general prosecution said the interrogation of a number of the accused would continue, adding that two requests asking for further evidence had been sent to Turkey but had not received any response.

The Saudi prosecution said that following the hearing in the case the defendants asked for a copy from the prosecutors and sought time to make their defence.

The Turkish president, Recep Tayyip Erdoğan, has asked for the accused to be extradited to Turkey to stand trial, a request that has been rejected.

Erdoğan has effectively accused the Saudi crown prince, Mohammed bin Salman, of ordering the killing of Khashoggi, a columnist for the Washington Post, and has run a persistent campaign revealing details of the Turkish police investigation into the murder that has kept Saudi Arabia on the diplomatic back foot.

The CIA has also told US Congress that it believes the crown prince ordered the killing. The episode has already led to a Saudi cabinet reshuffle, involving the partial demotion of the foreign minister, Adel al-Jubeir, and a reordering of the Saudi intelligence service seen to be at the heart of Khashoggi murder.

Jubeir was replaced by Ibrahim al-Assaf, an experienced figure who had previously served as finance minister.

In response to Khashoggi’s murder, Britain has asked that the Saudis reassure the world that such an event cannot be repeated, seen as a code that the crown prince will not be able to use the intelligence service as a personal tool to suppress dissent abroad.

The trial will be notable for the degree to which the defendants are able to set out in open court whether they were instructed by the state to carry out the murder, or instead had been instructed to repatriate Khashoggi, but on meeting resistance from the journalist chose to kill him.

Trials in Saudi Arabia are normally held behind closed doors so it is likely no claim that the hit team were acting on orders of the royal court will ever be aired.

The human rights group Reprieve estimates there have been nearly 700 executions in Saudi Arabia since 2014.

Saudi Arabia has provided sharply contrasting accounts of how Khashoggi came to die. On New Year’s Eve, Turkish police released new footage purporting to show bags containing Khashoggi’s body parts being carried into the home of the Saudi consul general in Istanbul. Turkish authorities have carried out numerous body searches in Turkey since the murder, but without success.

The Turkish network A Haber broadcast video showing the entrance to the gated residence of Saudi Arabia’s consul general in Istanbul, not far from the Saudi consulate. The footage shows men, their faces obscured by shadow, carrying several large suitcases or bags into the building. The Saudis have not allowed the garden’s well to be fully searched, or dried. The footage purportedly hows Maj Gen Mahir Abdul Aziz Muhammad Mutrib, an associate of the crown prince, helping with the movement of the bags.

The consul, Mohammed al-Otaibi, has returned to Riyadh, and has not been seen.

Turkey has also released a sound recording inside the consul general’s office in which Khashoggi resists suffocation. Subsequently a member of the Saudi team can be heard telling a superior over the phone to “tell your boss” that the mission had been achieved. That is believed to be a reference to the Saudi crown prince.