The United Nations says Secretary-General Antonio Guterres is "very concerned" about the disappearance of Saudi journalist Jamal Khashoggi and violence against other journalists.

Iran Press/Middle East: U.N. spokesman Stephane Dujarric said the U.N. chief is following the Khashoggi case "closely," noting that an investigation is taking place in Istanbul, Aljazeera reported.

Dujarric told reporters at U.N. headquarters in New York on Monday that Guterres "has been an advocate for journalists."

He says: "Both publicly and privately, the secretary-general has often raised this issue with member states."

General Assembly President Maria Espinosa Garces is also "very concerned" about Khashoggi's disappearance, spokeswoman Monica Grayley said.

Khashoggi, 59, a US resident, has written articles over the past year critical of Saudi Crown Prince Mohammed bin Salman. On the eve of his planned marriage to a Turkish woman, he entered the consulate on October 2 and has not been seen since.

Turkish officials say Jamal Khashoggi was killed at the Saudi Consulate in Istanbul and that his body was later removed from the building, without providing evidence. Saudi officials have denied the allegations, and the consulate says Khashoggi left its premises.

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Saudi journalist killed inside consulate: Turkish authorities

Saudis "cannot save themselves by saying he left"

Speaking during a visit to Hungary, Turkish President Recep Tayyip Erdogan said on Monday that Saudi Arabia has the responsibility to prove its claim that a missing Saudi journalist left the Saudi Consulate in Istanbul.

Erdogan said the Saudis "cannot save themselves by saying he left."

Turkish President stressed that police, intelligence and judiciary officials are investigating, and he himself was following the investigation, saying it was his political and humanitarian duty.

Turkey has summoned Saudi Arabia's ambassador to Ankara for the second time in less than a week and asked for permission to search the kingdom's consulate for dissident journalist Jamal Khashoggi.

Related news: Turkey summons Saudi AMB for second time

Turkish officials claim the Washington Post contributor was slain at the consulate and that his body was later removed. President Recep Tayyip Erdogan did not confirm the alleged killing saying he would await the result of an investigation.

Saudi officials have denied the allegations as baseless.

Devastating to the US-Saudi relationship

Republican Senator Lindsey Graham said Riyadh must provide “honest answers” about the journalist. We agree that if there was any truth to the allegations of wrongdoing by the Saudi government it would be devastating to the US-Saudi relationship and there will be a heavy price to be paid – economically and otherwise,” Graham tweeted.

US Secretary of State Mike Pompeo called for a thorough and open probe by Saudi Arabia.    

"We call on the government of Saudi Arabia to support a thorough investigation of Khashoggi's disappearance and to be transparent about the results of that investigation," Pompeo said in a statement.

US President Donald Trump told reporters at the White House that “I am concerned. I don’t like hearing about it. Hopefully that will sort itself out. Right now, nobody knows anything about it. There are some pretty bad stories going around. I do not like it.”

Several Western countries, specially United States are supplying the Riyadh regime with advanced weapons and military equipment.

Last year, Trump signed the largest arms deal in history with the Arab country despite warnings that he could be accused of being complicit in the regime's war crimes in Yemen.

Earlier this month Saudi crown prince said in a Bloomberg interview that “Actually we will pay nothing for our security. We believe that all the armaments we have from the United States of America are paid for, it’s not free armament," the Saudi crown prince said in a Bloomberg interview conducted on Wednesday and published on Friday.

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Bin Salman: We pay nothing to US for our security

The 33-year-old crown prince went on to say that Saudi Arabia had agreed to buy $110 billion worth of US weapons and signed investment deals worth billions more, some “$400 billion” in total, since Trump took office in early 2017, and described the deals as “a good achievement" for Trump.

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