WASHINGTON (Reuters) - The outcry in the United States demonizing Saudi Arabia over the murder of Saudi journalist Jamal Khashoggi in the kingdom’s consulate in Istanbul threatens U.S.-Saudi strategic ties, the former Saudi intelligence minister warned on Wednesday.

Friends of Saudi journalist Jamal Khashoggi hold posters and banners with his pictures during a demonstration outside the Saudi Arabia consulate in Istanbul, Turkey October 25, 2018. REUTERS/Osman Orsal/File Photo

“We value our strategic relationship with the United States and hope to sustain it. We hope the United States reciprocates in kind,” royal family member Prince Turki bin Faisal al Saud said in an address to the National Council on U.S.-Arab Relations, a non-profit advocacy organization.

Turki, to whom Khashoggi once served as an adviser, has also served as an ambassador to London and Washington. His speech denouncing what he called “the demonization of Saudi Arabia” clearly carried Riyadh’s imprimatur, as he heads an Islamic research center named after his father, the late King Faisal.

Turki’s address came after Istanbul’s chief prosecutor on Tuesday said that Khashoggi was suffocated in a premeditated killing and his body was then dismembered.

Khashoggi, who lived in self-imposed exile in the United States, wrote columns for the Washington Post critical of the kingdom’s de facto ruler, Crown Prince Mohammed bin Salman.

Some U.S. lawmakers have accused the crown prince of ordering Khashoggi’s death - a charge that Riyadh denies - and threatened sanctions. U.S. commentators have strongly condemned the kingdom.

Recalling that more than 70 years of U.S.-Saudi ties survived previous crises, Turki said, “Nowadays, this relationship is once again threatened.”

“The tragic and unjustified” slaying of Khashoggi “is the theme of today’s onslaught and demonization of Saudi Arabia in the same fashion as the previous crises. The intensity and gleefulness of it is equally unfair,” he said. “Subjecting our relationship to this issue is not healthy at all.”

Turki reiterated that the kingdom is committed to bringing to justice those responsible for Khashoggi’s murder “and whoever else failed to uphold the law.”

The Trump administration is demanding full accountability from Riyadh in Khashoggi’s death. In what it called a first step, it revoked the visas of some Saudi officials implicated in the slaying.

The U.S.-Saudi relationship “is too big to fail,” Turki said.

Those ties, he noted, transcend oil production, trade, arms sales and investment to cooperation on Middle East peace efforts, stabilizing oil markets, fighting extremism and containing Iran, the kingdom’s main regional foe.