Nabil Fahmy, a former Egyptian ambassador to the United States, has accepted the post of foreign minister in the interim government being put in place after the army overthrew president Mohamed Morsi earlier this month.
Fahmy, who announced his acceptance on Sunday, is a member of the opposition, AlDostour (the constitution) Party, led by Mohamed ElBaradei.
Meanwhile, ElBaradei, who led the country's main opposition group in criticism of the Muslim Brotherhood, was sworn-in as the country's interim vice president.
The 71-year-old former diplomat and Nobel laureate emerged as a prominent democracy advocate and later as the head of the National Salvation Front, a secular coalition of groups opposed to the deposed President.
According to NSF spokesman Khaled Dawoud, ElBaradei no longer heads the coalition.
Interim Prime Minister Hazem el-Beblawi has began to assemble a government expected to be made up mainly of technocrats and liberals to lead Egypt under an army-backed "road map" to restore full civilian rule.
Fahmy is the founding Dean of the School of Public Affairs at the American University in Cairo.
A career diplomat, Fahmy was Egypt’s ambassador to the US from 1999 to 2008. He also served as Egypt’s ambassador to Japan and as the political adviser to the foreign minister during the mid-90s.
Critical of Morsi
In an interview given to Al Jazeera on the one-year anniversary of Morsi’s presidency, Fahmy was critical of the leader's foreign policy.
Fahmy argued that foreign policy under Morsi had been motivated by Egypt's economic challenges, and the need to attract investment.
Fahmy also highlighted Morsi's moves during the Israeli assault on Gaza in November 2012.
"I believe Morsi initially succeeded in calming the situation on the war front between Israel and Gaza," he told Al Jazeera.
Earlier on Friday, Beblawi said he had nominated lawyer Ziad Bahaa el-Din, a member of the leftist Egyptian Social Democratic Party, as deputy prime minister.
Another leftist politician, the former supply minister Abdel Khalek, said he had declined an offer to return to the post, citing personal reasons.
Morsi's Muslim Brotherhood have rejected offers to become a part of the new cabinet, vowing to continue defying what they say is a military coup.