Several US citizens barred from leaving Egypt are sheltering at the US embassy in Cairo, the state department says.
Ten foreigners, including six US nationals were stopped from leaving Egypt. Among them is Sam LaHood, son of US Transport Secretary Ray LaHood.
It is unclear if Sam LaHood is among those taking refuge at the US embassy.
The generals who took power after President Hosni Mubarak was deposed last year accuse "foreign hands" of funding protests against their rule.
The foreigners are being held in Egypt during a criminal investigation of US-funded organisations at which they worked. Critics say the inquiry is an attempt to silence critics of the army's crackdown on street unrest.
"We can confirm that a handful of US citizens have opted to stay in the embassy compound in Cairo while waiting for permission to depart Egypt," state department spokeswoman Kate Starr told reporters in Washington on Monday.
Cairo has faced criticism from Washington over its decision to investigate the activities of a number of civil society organisations operating in Egypt.
The travel ban followed a raid by the Egyptian authorities in December of democracy groups that receive foreign funding.
The organisations affected include the International Republican Institute - where Mr LaHood was working - and its sister group the National Democratic Institute.
Both of the bodies - which receive US public funding and have links with the Republican and Democratic parties - monitored Egypt's recent parliamentary elections.
In a weekend call to Field Marshal Hussein Tantawi, head of Egypt's ruling military council, US Defense Secretary Leon Panetta urged the travel ban lifted, the Pentagon said.
Washington has warned it could review US aid to Egypt's military, about $1.3bn (£826m) annually, unless it respects non-governmental groups.
US President Barack Obama raised the issue with the field marshal earlier this month during a call when he also discussed Egypt's request for a $3.2bn loan from the IMF.