President Mohamed Morsi has declared a state of emergency in three provinces hit by rioting which has left dozens dead, warning he was ready to take further steps to confront threats to Egypt's security.
Emergency measures will come into effect in the provinces of Port Said, Suez and Ismailia 'for 30 days starting at midnight', Mr Morsi said in an address on state television.
Curfews would be imposed on the same three provinces from 9pm until 6am, he added.
He warned that he was ready to take further measures if the deadly violence that swept over Egypt since Friday does not end.
He also held out an olive branch to the opposition and political leaders across Egypt, inviting them for talks saying 'there is no alternative to dialogue'.
He added in his brief address: 'There is no going back to freedom and democracy ... the rule of law and social justice that the revolution has paved.'
The opposition has threatened to boycott the coming parliamentary polls if President Morsi did not find a
'comprehensive solution' to the unrest.
The National Salvation Front, the main coalition of parties and movements opposing the ruling Islamists, said it would 'not participate' in the polls unless a 'national salvation' government was formed.
Mr Morsi's comments came after rioting sparked by death sentences being passed on fans of a local football team rocked Egypt's Port Said for a second successive day, leaving another six people dead and more than 460 injured, according to medics.
Crowds attempted to storm three police stations in the canal city and others torched a social club belonging to the armed forces, looting items inside, security officials said.
The latest casualties, among the six a teenager shot in the chest, add to the toll of 31 people including two anti-riot police killed on Saturday in the Mediterranean city.
Unrest also erupted on Sunday in Suez, another canal city, where protestors surrounded a police station, lobbed Molotov cocktails at security forces and blocked the road leading to the capital, security officials said.
And in the capital, clashes broke between police and protestors who accuse President Morsi of betraying the goals of the revolution that ousted former President Hosni Mubarak two years ago, highlighting deep political divisions in the country now ruled by Islamists.
The rioting in Port Said began on Saturday after a Cairo court handed down death sentences on 21 supporters of the local football club, Al-Masry, in the wake of football violence in 2012 that left 74 people dead.
Morsi insisted that the verdicts that triggered the violence 'must be respected by all of us'.
He condemned the violence as 'a violation of the law and a violation of the revolution'.
The President also said he had instructed the interior ministry to 'use all decisive force against those who attack the security of the people, government buildings, those who use weapons, block roads, those who throw stones on innocents...'