Egypt's government has resigned, the prime minister said on Monday, a step likely to pave the way for army chief Field Marshal Abdel Fattah al-Sisi to declare his candidacy for president.

"(The government) made every effort to get Egypt out of the narrow tunnel in terms of security, economic pressures and political confusion," Prime Minister Hazem el-Beblawi said in a live nationwide speech.

Beblawi, who was tasked by interim President Adly Mansour with running the government's affairs until the election, did not give a clear reason for the decision.

For Sisi to run for president, he would first need to quit as defence minister. "This (government resignation) was done as a step that was needed ahead of Sisi's announcement that he will run for president," an Egyptian official told Reuters.

He said the cabinet resigned en masse as Sisi did not want to appear to be acting alone.

The top military commander has unveiled a political roadmap meant to lead to elections after toppling Islamist President Mohamed Mursi of the Muslim Brotherhood in July following mass protests against his rule.

The vote is expected within months in Egypt, which has great geo-strategic importance due to its peace treaty with Israel and control over the Suez Canal, a vital global shipping lane that is the shortest between Asia and Europe.

Egypt's stock market rose 0.26 percent after news of the government's departure to 8029.37 points, reversing losses from earlier in the day.

Mursi's removal triggered the bloodiest political crisis in Egypt's modern history, with security forces killing hundreds of Brotherhood supporters, jailing thousands and putting top leaders on trial.

Compounding the instability, Islamist militants based in the widely lawless Sinai Peninsula have stepped up attacks on police and soldiers, killing hundreds. - Reuters