Five Republican US senators have called on Donald Trump to suspend talks to reach a civil nuclear cooperation agreement with Saudi Arabia over the recent killing of journalist Jamal Khashoggi.
In a letter sent to the US president on Wednesday, the politicians said they were concerned by Riyadh's ongoing refusal to adopt policies and technologies that limit the enrichment of uranium and reprocess plutonium, among other nuclear fuel-making activities.
However, the killing of Khashoggi, a prominent Washington Post columnist, on 2 October at the Saudi consulate in Istanbul raises questions about the current thinking of Saudi decision-makers, they said.
"The ongoing revelations about the murder of Saudi journalist Jamal Khashoggi, as well as certain Saudi actions related to Yemen and Lebanon, have raised further serious concerns about the transparency, accountability and judgment of current decisionmakers in Saudi Arabia," the letter reads.
The letter was signed by five Republican senators, including Marco Rubio and Rand Paul, who have been very vocal in their criticism of Saudi Arabia in the aftermath of Khashoggi's murder.
Four of the senators - Rubio, Paul, Cory Gardner and Todd Young - are on the powerful Senate Committee on Foreign Relations, which writes legislation related to foreign policy.
The senators said they would block "any agreement at this time" in light of their concerns.
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Trump has been under increasing pressure to hold Saudi Arabia - and Crown Prince Mohammed bin Salman, in particular - accountable for the death of Khashoggi.
Asked Wednesday if he believed the Saudis had betrayed him, in relation to the Khashoggi case, Trump responded: "They haven't betrayed me... maybe they have betrayed themselves".
"We'll have to see how it all turns out," the president said.
A Saudi insider-turned-critic, Khashoggi was killed and dismembered in the Saudi consulate in Istanbul earlier this month.
After weeks of denials and changing accounts of what happened, Saudi officials recently said Khashoggi's murder was premeditated.
Critics have demanded that Saudi Arabia reveal the full truth, however, saying its latest version of events lacks credibility.
Meanwhile, the journalist's fiancee, Hatice Cengiz, recently called on the Saudis to release Khashoggi's body and for a " real investigation " to be launched.