US Secretary of State John Kerry Saturday spoke with Egypt's interim Vice President Mohamed ElBaradei to express "deep concern about the bloodshed and violence", dpa reported.
Kerry also spoke with interim Foreign Minister Nabil Fahmy.
US Secretary of Defence Chuck Hagel spoke with his Egyptian counterpart Abdel-Fattah al-Sissi to "encourage that restraint be exercised during this difficult period," according to a statement issued by the Pentagon.
"The United States believes that the current transition needs to be marked by inclusivity, that Egyptian authorities should avoid politicized arrests and detentions, and take steps to prevent further bloodshed and loss of life."