there http://cousinscandy.net/components/com_k2/templates/generic_search.php geneva;”>Mr Mansour said fresh elections were “the only way” forward, this site but gave no indication of when they would be held.
Mr Morsi, Egypt’s first freely elected leader, is under house arrest after what he says was a military coup.
The army said he had “failed to meet the demands of the people”.
The upheaval comes after days of mass rallies against Mr Morsi and the Islamist Muslim Brotherhood movement he comes from.
Protesters accused them of pursuing an Islamist agenda and of failing to tackle Egypt’s economic problems.
The health ministry says at least 10 people were killed and scores injured in clashes at rival protests across the country overnight. Some 50 people have died since the latest unrest began on Sunday.
Mr Mansour was sworn in as chief justice of the Supreme Constitutional Court on Thursday morning, then, shortly after, he took the oath to become interim head of state, vowing to “preserve the system of the republic, and respect the constitution and law, and guard the people’s interests”.
He said he would safeguard “the spirit of the revolution” which removed Hosni Mubarak from power in 2011, and would “put an end to the idea of worshipping the leader”.
Elections would be held based on “the genuine people’s will, not a fraudulent one,” he said. “This is the only way for a brighter future, a freer future, a more democratic one”.
Mr Mansour also praised the military as “the conscience of the nation and the guarantor of its security and safety”.
He and the main leftists alliance, the National Salvation Front, later said the Muslim Brotherhood was welcome to take part in the conversation on Egypt’s future.
However Gehad el-Haddad, a spokesman for the Muslim Brotherhood, told the BBC that Mr Morsi had been put under house arrest and the “entire presidential team” was in detention.
Mr Haddad’s father, senior Morsi aide Essam el-Haddad, and Saad al-Katatni, head of the Brotherhood’s political wing, are among those held.
The state-run al-Ahram newspaper reported that arrest warrants had been issued for 300 leaders and members of the Muslim Brotherhood.
The BBC’s Shaimaa Khalil in Cairo says the Brotherhood is refusing to acknowledge the change in power and is planning to hold rallies across the country.