Egypt's newly elected president has sent an implicit message of reassurance to Israel in his first major address after taking office, but he also pledged support for the "legitimate rights" of the Palestinians.

Islamist Mohammed Morsi said Saturday that his administration will continue to honor its international treaties - a thinly veiled reference to the Egyptian-Israeli peace treaty.

Morsi promised a "new Egypt" as he was inaugurated as the Arab world's first freely elected Islamist president, became Egypt's fifth head of state since the overthrow of the monarchy some 60 years ago.

He took the oath before Supreme Constitutional Court in its Nile-side seat built to resemble an ancient Egyptian temple.

"We aspire to a better tomorrow, a new Egypt and a second republic," Morsi told the judges of the court after taking the oath in a solemn ceremony shown live on state television.

"Today, the Egyptian people laid the foundation of a new life - absolute freedom, a genuine democracy and stability," said Morsi, a 60-year-old U.S.-trained engineer.

Relations between Israel and Egypt have become particularly tense since last year's overthrow of Morsi's predecessor, Hosni Mubarak, who had forged close ties with the Jewish state during his 29-year rule.

On Sunday, Egypt's state election committee declared Morsi the winner of a runoff presidential election with 51.7 percent, defeating former prime minister Ahmed Shafiq.