In a carefully worded statement, Obama said he was "deeply concerned" by the military's move to topple Morsi's government and suspend Egypt's constitution. He said he was ordering the US government to assess what the military's actions meant for US foreign aid to Egypt — $1.5 billion a year in military and economic assistance.

Under US law, the government must suspend foreign aid to any nation whose elected leader is ousted in a coup.

"I now call on the Egyptian military to move quickly and responsibly to return full authority back to a democratically elected civilian government as soon as possible through an inclusive and transparent process, and to avoid any arbitrary arrests of President Morsi and his supporters," Obama said.

The US wasn't taking sides in the conflict, committing itself only to democracy and respect for the rule of law, Obama said.

Egyptian armed forces on Wednesday ousted Morsi, an Islamist and Egypt's first democratically elected president, after just a year in power. The military installed a temporary civilian government, suspended the constitution and called for new elections. Morsi has denounced it as a "full coup."