But many Egyptians, and anxious Western allies, also urged Mursi to work fast to repair the economy and bitter divisions in society exposed since the overthrow of Hosni Mubarak fractured the police state which had kept the country subdued for decades.
Mursi defeated former general Ahmed Shafik in a run-off last weekend by a convincing 3.5 percentage points, or nearly 900,000 votes, taking 51.7 per cent of the total, officials said. It ended a week of disputes over the count that had frayed nerves.
Mursi succeeds Mubarak, who was pushed aside by his fellow officers 16 months ago to appease the Arab Spring revolution.
“I congratulate the Egyptian people for their commitment to the democratic process and electing a new President of Egypt. I wish Dr Mohammed Mursi success in the challenging task ahead,” said foreign secretary William Hague.