The 20 suspects will be searched across the world.
The notice was issued on March 1 as part of Turkey's request over the investigation launched into the murder by the Istanbul Chief Public Prosecutor's Office.
Turkey urged Saudi Arabia to extradite the perpetrators, as well as to provide information about the location of Khashoggi's body.
Bandar bin Mohammed al-Aiban told the UN Human Rights Council that those on trial for the "heinous crime" and "unfortunate accident" at its Istanbul consulate on Oct 3 had attended three hearings so far with their lawyers present.
After making numerous contradictory statements, it said Khashoggi was killed after negotiations to persuade him to return to Saudi Arabia failed - and later that 11 Saudis had been indicted and referred for trial over the case, without identifying them. It said earlier on Thursday that Saudi authorities should disclose the names of defendants and the charges they face if it wanted to avoid questions over the "sincerity of judicial proceedings in the kingdom". He gave no names or other details.
Aiban also rejected any outside probes into what happened to Khashoggi.
"Justice in the kingdom of Saudi Arabia operates pursuant to worldwide law and it does so in all transparency, " al-Aiban told the forum, right before adding that the Kingdom would not accept any "foreign interference" in its "domestic affairs or judicial system".
Regarding Yemen's crisis, he said the Arab Coalition is committed to worldwide human rights law.
"Justice in the kingdom of Saudi Arabia operates pursuant to worldwide law and it does so in all transparency", Aiban told the Geneva forum during a review of Saudi Arabia's rights record.
On Thursday, critics of the government's handling of the investigation, including Yahya Assiri, a Saudi human rights activist, noted the omission of any mention of the kingdom's powerful crown prince.
The CIA concluded late previous year that bin Salman ordered the journalist's assassination, an accusation that has been echoed by United States senators and other observers.
"Saudi Arabia is a sovereign country".
Will Saudi Arabia comply with global human rights law and its membership obligations by immediately releasing all human rights activists jailed for advocating peaceful reform, removing government-enforced travel restrictions for women, declaring a moratorium on the death penalty, starting with those convicted of non-violent drug offenses, and fully cooperating with the UN Special Rapporteur on extrajudicial, summary or arbitrary executions on her inquiry into the Khashoggi murder, and with the Yemen Group of Eminent Experts?
They also condemned Khashoggi's murder "in the strongest possible terms".