US Secretary of State Hillary Clinton has held her first meeting with new Egyptian President Mohammed Mursi.
After the talks, she reaffirmed Washington's support for a "full transition to civilian rule" in Egypt.
President Mursi has become embroiled in a constitutional crisis after trying to reinstate a parliament dissolved by the judiciary and the military.
Mrs Clinton has backed Mr Mursi, saying Egyptians should get the government they voted for.
Mr Mursi, of the Muslim Brotherhood's Freedom and Justice Party, was elected in June in the country's first ever freely contested leadership vote.
After the meeting in Cairo, Mrs Clinton told reporters: "I have come to Cairo to reaffirm the strong support of the United States for the Egyptian people and their democratic transition.
"We want to be a good partner and we want to support the democracy that has been achieved by the courage and sacrifice of the Egyptian people."
The BBC's Jon Leyne, in Cairo, says that not many years ago, one US secretary of state declared that Washington did not speak with the Muslim Brotherhood, and never would.
But, he says, the administration of Barack Obama has been quick to engage with the new president - a case of accepting the inevitable and trying to make the best of it.
The US government wants to see Egyptian democracy and human rights being protected.
The Muslim Brotherhood has repeatedly stressed it does not want to be isolated internationally, not least because the country depends so heavily on international trade and tourism.
Mr Mursi has tried to defuse the row over parliament - a body he tried to reinstate by decree last weekend.
The chamber was dominated by Mr Mursi's Islamist allies, and was shut down by the military before he took power.
The Supreme Constitutional Court has said the dissolution is final.
Mr Mursi has said he is "committed to the rulings of Egyptian judges and very keen to manage state powers and prevent any confrontation".
Mr Clinton said she would meet the head of the Supreme Council of the Armed Forces (Scaf), Field Marshal Mohammed Hussein Tantawi, on Sunday.
He became the country's interim ruler after the fall of President Hosni Mubarak in February last year.
Asked what she would tell Field Marshal Tantawi, Mrs Clinton said she would make clear the US supports the return of the armed forced "to a purely military role".
Earlier this week, Mrs Clinton said Egyptians should "get what they protested for and what they voted for, which is a fully-elected government making the decisions for the country going forward".
Mrs Clinton arrived in Egypt from a week-long trip to Asia, and will later visit Israel.
Source: BBC News