CAIRO -- President Mohamed Morsi of Egypt gave the army police powers to make arrests on Thursday, an official from his party said, while tanks and soldiers beefed up security near government buildings and the strategic Suez Canal in anticipation of mass protests planned for this weekend that many fear will unleash a new wave of unrest.
The competing calls for protests this weekend reflect the deep and bitter divide over how Egypt has been run since the revolution that toppled President Hosni Mubarak in 2011.
On one side are Mr. Morsi, the Muslim Brotherhood and their Islamist allies who say their victories in the post-revolutionary elections legitimize their standing and express the popular will. Challenging them is a disparate opposition that accuses Mr. Morsi and his allies of excluding non-Islamist voices from the post-revolutionary transition and failing to alleviate the country's growing economic distress.
Opposition protests and counterprotests are scheduled to kick off Friday and continue through Sunday, the anniversary of Mr. Morsi's inauguration. Opposition activists have vowed to remain in the streets until Mr. Morsi stands down.
Reflecting fears that the protests could turn violent, the army has been deploying tanks and soldiers near government ministries, the central bank and at the entrances to some Cairo neighborhoods. It has also enhanced security in cities along the Suez Canal.
New weapons have been distributed to police officers, and police stations have transferred detainees held on site to central prisons, security officials said.
The American Embassy here in Cairo has repeatedly warned its citizens of the potential for violence between protesters and will remain closed on Sunday, normally the first day of the Egyptian workweek.
Mr. Morsi and his Freedom and Justice Party also took steps on Thursday to enhance security.
A party official, Gehad El-Haddad, said in a post on Twitter on Thursday that Mr. Morsi had given the police and the army "judicial arrest powers to secure major government buildings" and to ensure law and order.
He also said that the party and the Muslim Brotherhood that founded it had hired private security companies to protect their headquarters.
Protesters have ransacked offices belonging to the two groups during past protests and sometimes engaged in bloody clashes with Brotherhood members.
Egypt's interior minister said in a recent TV interview that the police did not have the manpower to protect the offices of all of Egypt's political parties, but that they would intervene if violence occurred. Mr. Haddad said in another post on Twitter that the Brotherhood would use its "right of self-defense" if the police failed to protect its offices.
In a two-and-a-half-hour address Wednesday, Mr. Morsi offered no major concessions to defuse a campaign by opposition activists to push for his ouster while raising the specter of new political violence.
"The political polarization and infighting have reached a point that endangers our nascent democracy, and it threatens the whole country with a state of paralysis and chaos," Mr. Morsi said.
Mr. Morsi offered only scant concessions in his speech on Wednesday to those seeking his removal. He renewed his invitation to opposition figures to participate in amending the country's new Constitution and announced the formation of a body to discuss national reconciliation.
But the speech failed to blunt the opposition's charge.
"Dr. Morsi's speech has only increased our insistence on calling for an early presidential elections in order to achieve the revolution's goals, the foremost of which is social justice," Mohamed ElBaradei, a leader in the opposition's National Salvation Front said at a news conference on Thursday.
This article originally appeared in The New York Times.