A senior politician in Egypt's Muslim Brotherhood said on Thursday that the military overthrow of elected Islamist President Mohamed Morsi will push other groups, though not his own, to violent resistance.

"The issue is not with Brothers being in or out of prison. The Brothers have lived in prisons for ages," Mohamed El-Beltagy, a leading member of the Brotherhood's political arm, the Freedom and Justice Party, told reporters.

"The issue now is the position of the free world that is pushing the country to a state of chaos and pushing groups other than the Brotherhood to return to the idea of change by force," he said.

Beltagy was speaking at a sit-in by Morsi supporters at a suburban Cairo mosque close to the presidential palace.