(CNN) -- Egypt's military rulers granted the newly appointed prime minister most powers of the president Wednesday.
Prime Minister Kamal Ganzouri then swiftly swore in his cabinet.
Ganzouri was given all presidential powers except control over the military and the judiciary, armed forces spokesman Lt. Col. Amr Imam said.
On Tuesday, Ganzouri said on state television that "the new national government will be the salvation government of the January 28 revolution."
The new cabinet will serve until the presidential elections.
Opposition parties criticized the way the power transfer was playing out.
Ahmed Abu Baraka, the political advisor of the Muslim Brotherhood's Freedom and Justice Party, said the transfer amounted to "nothing but a political maneuver" by the country's military rulers "to attempt to appease the public opinion on the street after they have failed in running in the country during this interim period.
"This new cabinet will have to live up to the expectations of the revolution and only has a limited time before it's either reinstated again or replaced depending on their performance, and only the Egyptian people are to judge this," he said.
Rami Shaath, a member of the Egyptian Revolutionary Alliance, another opposition party, also had harsh words.
Giving "these so-called presidential powers to an 80-year-old prime minister and former member of Mubarak's NDP party do not mean anything to us," Shaath said. "He was chosen by the Supreme Council with no political base from Tahrir. When we demanded a national salvation government, we wanted a representative from the revolutionaries, not a puppet that serves the goals of the military who do not have right to choose him anyway."
He added, "The Supreme Council will continue to serve the need of the U.S. in the region over its people's demands."
A lengthy election process in Egypt began last Sunday with the first round of parliamentary voting.
Islamist parties appeared to make major inroads in that election.
The Muslim Brotherhood, an Islamist party widely seen as being relatively moderate, won more than 40% of the vote, while the more hard-line al-Nour party took as much as 25%.
While the Muslim Brotherhood has pledged to respect minority rights and work with liberal parties, concern has been focused on the success of al-Nour, a Salafist party that supports broader application of strict Islamic law in Egypt.
The election of a majority Islamist government could inflame tensions in the region and complicate key relationships, but analysts say the United States and other Western countries have a fine line to walk amid the first parliamentary elections since the fall of former Egyptian leader Hosni Mubarak earlier this year.
Journalist Mohamed Fadel Fahmy contributed to this report.