ABU DHABI (Reuters/AFP) - Egypt's armed forces, for decades at the center of power, will avoid involvement in politics but could have a role if things became "complicated", the chief of staff said on Sunday.

It also expects rival political groups to solve disputes by dialogue, Major General Sedki Sobhi told Reuters. The military ran Egypt for six decades from the end of the colonial era and through an interim period after the overthrow of former air force chief and president Hosni Mubarak two years ago.

About 60 people have been killed since late January in protests that erupted after the second anniversary of the uprising.

Speaking to Reuters at an industry event in Abu Dhabi, said that in a week or 15 days some kind of national dialogue would take shape between the ruling Muslim Brotherhood and opposition groups. The army would not back any political party, he said. "We are not political, we don't want to participate in the political situation because we suffered a lot because of this in the last six months," he said.

"But sometimes we can help in this problem, we can play this role if the situation became more complicated," he said without elaborating.

Diplomats and analysts suggest the army, fearful of further damaging a reputation that took a beating during a messy transition period when it was in charge, would only act if Egypt faced unrest on the scale of the revolt that toppled Mubarak. Protests and violence now are nowhere near that stage.

Sobhi's remarks were less categorical than those of General Abdel Fattah al-Sisi, the army chief, who said on January 29 that unrest was pushing the state to the brink of collapse and the army would remain the "solid and cohesive block" on which the state rests.

Asked about security in Egypt, Sobhi downplayed violence during protests earlier this month. "We cannot say it is a very serious or very dangerous," he said.

On Sunday, thousands closed down government offices and factories in the Suez Canal city of Port Said, demanding justice for dozens of people killed in clashes with police, witnesses said.

Demonstrators also shut down schools and banks and blocked a main railway route, but their protests did not impact traffic through the strategic Suez Canal, a canal official said.

The marchers were demanding justice for at least 40 protesters killed in clashes with police in late January after a court sentenced 21 soccer fans from the city to death over a deadly football riot last year.

In February 2012, 74 people, mostly supporters of the Cairo Al-Ahly club, were killed in a football riot in Port Said. Home fans were held to blame, with Al-Ahly supporters pledging civil disobedience in Cairo if the court acquitted the Port Said residents.

Last month's violence in Port Said and two other Suez Canal cities prompted President Mohamed Mursi to call in the military and declare emergency law there.

January's clashes coincided with the second anniversary of a popular uprising that overthrew president Hosni Mubarak, bringing in a period of military rule and then the Islamist Mursi's election last June.

Mursi has since had to contend with mass rallies led by a secular opposition and almost weekly violent protests by opponents of his Muslim Brotherhood movement.