Egyptian Islamists has warned the world to brace itself for a fierce backlash after an Egyptian court handed down a provisional death penalty to the nation's freely elected president, the Muslim Brotherhood's Mohamed Morsi, nearly two years after he was overthrown in a military coup in July 2013 following mass street protests against his rule.

Morsi and over 100 other people were sentenced to death on Saturday over a mass prison break during the 2011 uprising that toppled Morsi's predecessor, Hosni Mubarak. The ousted president was then convicted of conspiring with Hamas, the Brotherhood's Palestinian offshoot, whom judges decided had helped the prisoners leave jail in January 2011, reported The Guardian.

The sentence is provisional and will be carried out only if it is backed by the nation's religious leaders. A final decision is due to be announced on June 2.

Even if the execution is approved, analysts doubt that the Egyptian regime will carry out such a provocative act.

The sentence came as Morsi is already serving a 20-year-long jail term for arresting and torturing protesters while in power.

Morsi's supporters dubbed the decision as a form of "vengeance on the part of the regime," parts of which have reconstituted themselves under Morsi's usurper and former defence chief, Abdel Fatah al-Sisi.