Egypt's new President Mohamed Morsi issued a decree on Sunday annulling the Supreme Court's dissolution of the Islamist-dominated parliament, the official Mena news agency reported.
"President Morsi has issued a presidential decree annulling the decision taken on June 15, 2012 to dissolve the people's assembly, and invites the chamber to convene again and to exercise its prerogatives," Mena said.
It said the decree stipulates "the organisation of elections for the chamber, 60 days after the approval by referendum of the country's new constitution and the adoption of a new law regulating parliament."
Egypt's top court made the controversial move last month, a day before the second round of the presidential election that saw the Islamist Morsi become Egypt's first democratically elected head of state.
The Supreme Constitutional Court had said certain articles in the law governing parliamentary elections were invalid, annulling the Islamist-led house.
It also ruled as unconstitutional the political isolation law, which sought to bar senior members of ousted president Hosni Mubarak's regime and top members of his now-dissolved party from running for public office for 10 years.
Morsi beat Ahmed Shafiq -- Mubarak's last prime minister -- in the presidential election.
In the absence of a parliament -- in which nearly half of the seats had been won by the Muslim Brotherhood and another quarter by hardline Salafists -- the Supreme Council of the Armed Forces itself assumed legislative power.
The Brotherhood, formerly headed by Morsi, accused the SCAF of seeking to monopolise power and demanded a referendum.
Meanwhil,e President Barack Obama has invited Egypt's newly elected Islamist president to visit the United States in September, an Egyptian official said on Sunday, reflecting the new ties Washington is cultivating with the region's Islamists.
Washington, long wary of Islamists and an ally of ousted President Hosni Mubarak, shifted policy last year to open formal contacts with the Muslim Brotherhood, the group behind Mursi's win. Mursi formally resigned from the group after his victory.
Mursi's success at the polls mirrors the rising influence of Islamists in countries across the Middle East and North Africa in the wake of revolts and protests against autocratic rulers who have led the region for decades.
"President Obama extended an invitation to President Mursi to visit the United States when he attends the U.N. General Assembly in September," Egyptian aide Yasser Ali said after Mursi met U.S. Deputy Secretary of State William Burns in Cairo.
Burns, who did not mention the invitation at a news conference earlier, pledged U.S. support for Egypt's economy and said he welcomed Mursi's promise to uphold international treaties, which include a peace deal with Israel.
"We have taken careful note and appreciated President Mursi's public statements about a commitment to international obligations and we certainly attach great importance to Egypt's continuing role as a force for peace," Burns said.
Analysts say that one way the United States could influence the direction of policy in Egypt would be through economic support.
Washington provides $1.3 billion a year in military aid as well as other assistance and could help mobilise other donors, lenders and investors. Those could prove vital as Egypt tries to stave off a balance of payments and budget crisis.
"The United States is firmly committed to doing everything that we can to support Egypt's economic revival. We understand the challenges that lie ahead and also the president does," Burns told reporters after his two-hour meeting with Mursi.
Burns, whose trip precedes a visit to Egypt on July 14 by U.S. Secretary of State Hillary Clinton, said he had discussed a $3.2 billion loan package that Cairo has been negotiating with the International Monetary Fund.
"We talked in general terms about the value of moving ahead with the IMF in the interest of Egypt, trying to work out an equitable agreement that addresses Egypt's concerns and needs," he said.
He said the IMF package "can produce not only much needed resources but also sends an important positive signal to investors and donors and Egyptians as they move ahead on economic revival."