Egypt plans to put 19 American non-profit workers on trial before a criminal court for illegally using foreign funds to provoke unrest.
Among the Americans facing trial is Sam LaHood, son of U.S. Transportation Secretary Ray LaHood.
The United States has threatened to cut off aid to Egypt if it goes through with the trial.
"We will have to closely review these matters as it comes time for us to certify whether or not any of these funds from our government can be made available under these circumstances," Secretary of State Hillary Clinton said.
U.S. Ambassador to the United Nations Susan Rice told "CBS This Morning" that talks between Cairo and Washington have been ongoing "in the last days and hours."
She added that the situation "has serious consequences for our bilateral relationship."
Meanwhile, Egyptian officials are standing their ground, saying they will not interfere with the work of the judiciary.
All of those who are said to be under investigation are banned from leaving the North African country. They could face up to seven years in jail if convicted.