Senior representative of the European Union Catherine Ashton issued a statement on Tuesday expressing her concern over violence in Egypt over the past few days.

"I was deeply concerned by last weekend’s violent clashes in Egypt and yesterday’s terror attacks in Sinai and Ismailia. I extend my condolences to the victims and their families," read the statement.

Fifty-seven were killed on Sunday as supporters clashed with opponents of deposed president Mohamed Morsi and security forces on the 40th anniversary of the Arab-Israeli war in 1973.

Meanwhile on Monday, triple attacks left six army personnel dead in the city of Ismailia, and another two in southern Sinai in an attack on security headquarters. The third attack took place in Cairo's upscale district of Maadi, as armed assailants targeted an uplink telecom facility, used to air TV channels on Egypt's Nilesat satellite, with RPGs, resulting in minimal damage to the satellite dishes at the site but no casualties.

"The clashes show there is clearly a great deal of polarisation and mistrust. This can only be overcome if all sides commit to a political process, defined and agreed by Egyptians themselves, that leads to deep and sustainable democracy. During my visit last week, I saw some potential for this to happen," added Ashton, who stressed that the EU will continue to support Egypt.

Ashton arrived in Cairo for a three day visit at the beginning of the month, during which she met with several political forces, including the Muslim Brotherhood, General Commander of the Armed Forces Abdel-Fatah El-Sisi and interim President Adly Mansour.

Analysts have interpreted Ashton's three-day visit to Cairo as a renewed attempt to broach a settlement between the transitional government and the Muslim Brotherhood, who are at odds since the ouster of Mohamed Morsi by the military on 3 July, amid mass protests demanding his removal.

Ashton has visited the country twice since Morsi's ouster. She was the first foreign leader to be allowed to meet with the former president at the undisclosed location in which he is being held by Egyptian security forces.