Judge Mahmoud Shukry stated that the trial would resume on April 26, allowing the defendants to stay out of jail until the next hearing.
A total of 43 foreign and Egyptian activists, including the son of the US Transportation Secretary Ray LaHood, have been accused of receiving illegal funds and carrying out political activities in Egypt.
The 16 Americans have been barred from leaving Egypt and seven of them have sought asylum at the US Embassy in Cairo.
According to a US official who spoke on condition of anonymity, US Secretary of State Hillary Clinton met Egyptian Foreign Minister Mohamed Kamel Amr twice in the past three days.
The case has underscored tensions between the US and Egypt.
US authorities have threatened to cut a USD 1.5 billion annual aid package to Egypt if the issue is not resolved.
Many Egyptians suspect that the US is instigating the recent unrest in the country, by funding civil society groups in Egypt.