The statement is the first public allegation by Turkish law enforcement that Khashoggi was strangled and dismembered after he entered the Saudi Consulate on October 2 to collect paperwork that he needed to marry his Turkish fiancee.
Lawmakers led by Marco Rubio of Florida said in a letter to the president that they had reservations about the transfer of nuclear power technology even before the October 2 slaying of Khashoggi at the Saudi Consulate in Istanbul.
On Monday, Al-Muajab had an extensive meeting with Turkey's Chief Public Prosecutor Irfan Fidan at the Istanbul Caglayan courthouse.
The body of Saudi journalist Jamal Khashoggi was dismemberedafter he was strangled as soon as he entered the Saudi consulate in Istanbul, the chief prosecutor's office in Istanbul said Wednesday.
The prosecutor, in a statement said that no concrete results were reached in talks between him and Saudi public prosecutor Saud al-Mojeb.
"We therefore request that you suspend any related negotiations for a U.S. -Saudi civil nuclear agreement for the foreseeable future", said the lawmakers, who included senators Cory Gardner, Rand Paul, Dean Heller and Todd Young.
Celik also said it was not possible that Saudi officials had still not found the journalist's body after almost a month of investigations.
Over the period - which was either side of the last general election - Saudi Arabia was the government that spent the most on visits by MPs, followed by Taiwan and Hong Kong.
The comments appear to signal France upping the pressure on Saudi authorities, having so far declined to openly criticise the Riyadh regime over a death that has badly strained relations between the Middle East kingdom and the West.
Turkey, through a gradual release of information and public statements, has helped feed an global outcry over the case and pressured Saudi Arabia to concede its role.
He entered the consulate to obtain paperwork for his marriage to his Turkish fiancee Hatice Cengiz. The Turkish authorities had released a video evidence of him entering the Saudi consulate in Istanbul.
Trump has called the case "one of the worst cover-ups in history", but warned against halting a Saudi arms deal to increase pressure on Riyadh, saying it would harm USA jobs.
In a sign of the pressure on the Saudi leadership to change course, top US officials on Wednesday demanded peace talks within a month to end the Yemen conflict.
Turkish sources have told Middle East Eye that the journalist was cut into 15 pieces, at least one of which was thought to have been brought back to Saudi Arabia by one of the crown prince's bodyguards. What do the Saudis know about who planned the murder?