"We call on the government of Saudi Arabia to support a thorough investigation of Mr. Khashoggi's disappearance and to be transparent about the results of that investigation".
Khashoggi, journalist and columnist for The Washington Post, has been missing since he entered the Saudi Consulate in Istanbul on October 2.
Turkish officials have also claimed he was killed and other reports say Saudi Arabia sent a 15-member team to carry out a "pre-planned murder". It goes without saying that his family in the Kingdom remain gravely concerned about him, and so are we.
Protesters hold a portrait of missing journalist and Riyadh critic Jamal Khashoggi reading "Jamal Khashoggi is missing since October 2" during a demonstration in front of the Saudi Arabian consulate on October 9, 2018 in Istanbul. I don't like hearing about it.
Khashoggi, 59, had a long career as a senior journalist in Saudi Arabia and also as an adviser to top officials. Erdogan's response is likely to become more pointed in the coming days if there is no movement on issues that matter more to him than the disappearance of a foreign national inside Turkey. "If he's in Saudi Arabia, I would know that".
Now a source close to the Saudi royals has told DailyMail.com that an alternative version of events is being discussed inside high levels of the Saudi government.
The Washington Post columnist entered the Saudi consulate in Istanbul to get documents for his forthcoming marriage while his Turkish fiancee waited outside for him.
A group of 15 people from Saudi Arabia including some officials arrived in Istanbul in two planes and entered the consulate the same day Khashoggi was there and later left the country.
After several of his friends were arrested, his column was cancelled by the al-Hayat newspaper and he was allegedly warned to stop tweeting, Mr Khashoggi left Saudi Arabia for the USA, from where he wrote opinion pieces for the Washington Post and continued to appear on Arab and Western TV channels.
Turkish security sources confirmed the newspaper's report to MEE, and added that "there were intensive moves in and out of the consulate" last Tuesday.
Republican Senator Lindsey Graham said Riyadh must provide "honest answers" about the journalist. "I know what everybody else knows - nothing", Trump said. It is suspected that the "murder" was possibly the handiwork of Saudi agents, and that the operation was conducted in order to silence Khashoggi.
"If this is true - that the Saudis lured a U.S. resident into their consulate and murdered him - it should represent a fundamental break in our relationship with Saudi Arabia", he tweeted Sunday.
The mainstream is pointing to Donald Trump's close ties to the 33-year-old Crown Prince, without noting that support for the Saudi regime is longstanding and bipartisan; in 2011 Barack Obama approved $60 billion in arms sales to the kingdom, up to that point the largest weapons transaction in history.
A statement on Sunday by the state-run Saudi Press Agency (SPA) cited a diplomatic officer who categorically denied "these baseless allegations, and expressed his doubt that they came from Turkish officials that are informed of the investigation or are authorised to comment on the issue".