Earlier in the day, Mnuchin told reporters that he will make a decision on Thursday on whether to attend the October 23-25 conference in Riyadh after reviewing Secretary of State Mike Pompeo’s assessment of the situation. Pompeo visited Saudi Arabia earlier this week to discuss the Khashoggi case with government officials.
"We strongly urge you [Mnuchin] not to attend the Future Investment Initiative [FII] conference in Riyadh in light of the disappearance and alleged murder of Jamal Khashoggi by Saudi officials in their consulate in Istanbul," the letter said on Wednesday.
The United States, the letter added, must not turn a blind eye to the Saudi government’s behavior due to short-term economic gains from arms deals as suggested by US President Donald Trump.
The letter to Mnuchin was signed by US Congressmen Earl Blumenauer, Frank Pallone, and ten other House Democrats.
Turkish authorities said they have evidence Khashoggi was killed inside the Saudi consulate in Istanbul earlier this month. On Tuesday, the New York Times reported that Turkish authorities have been able to identify by name five of 15 suspects allegedly involved in Khashoggi’s death, four of whom have ties to the Saudi government.