There were no signs that any side in the complicated conflict was willing to heed her calls. The Brotherhood rejected calls to work with the new leaders and called for new demonstrations on Tuesday, the government made no conciliatory gestures, and Morsi remained in custody in an unknown location. He has not been seen since the military coup that ousted him on July 3.
On Monday Ashton began a three-day mission, her second since the military made its move.
Ashton's visit and calls by U.S. Secretary of State John Kerry underscored the sense of urgency in the international community, whose leaders are pushing for an inclusive political process that puts an end to violence.
In a sign of tensions and lawlessness that have gripped Egypt during two years of political turmoil, a dispute ended with the deaths of 15 people late Monday in Cairo. A shopkeeper shot and killed two men who spread goods in the ground in front of his store. Their colleagues set fire to the store, killing the man and 13 of his workers, police said.
Ashton made no comments after her meetings Monday with the defense chief, Gen. Abdel-Fattah el-Sissi, the interim president, Adly Mansour and his vice president, Mohammed ElBaradei. She also met for more than an hour with representatives from Morsi's Muslim Brotherhood.
U.S. State Department spokeswoman Jen Psaki said Kerry spoke with Ashton and Egyptian leaders on Monday, reinforcing her message for inclusiveness.
"I think we've been very clear that we believe an inclusive process means the participation of all parties. And certainly the detainment of many members of the Muslim Brotherhood, including Mr. Morsi, makes it difficult to move forward with that," Psaki told reporters in Washington.
She said the U.S. believes that Ashton should have access to Morsi while she is in Egypt.
The Brotherhood and its allies insist that Morsi must be returned to office.
They have also sustained their protest movement, calling for mass rallies Tuesday under the banner, "Martyrs of the Coup," and setting up a tent Monday a block away from their main sit-in for prayers for those killed over the weekend.
Despite the demonstrations, the military-backed government is pushing ahead with a transition plan to lead to elections early next year. At the same time, security officials and pro-military media have increasingly depicted the Islamists' protests as a threat to public safety.
After their talks with Ashton, a delegation of Islamist politicians representing the pro-Morsi camp said those now in power must take the first step toward any reconciliation by releasing jailed Brotherhood leaders, ending crackdown on their protests and stopping media campaigns against Islamists.
"Creating the atmosphere requires those in authority now to send messages of reassurance," Mohammed Mahsoub, of the Islamist Wasat Party, told reporters.
One of the thorniest issues toward reconciliation is the detention of several Brotherhood leaders and other prominent Islamists since Morsi's ouster.
On Sunday, authorities arrested two figures from the Brotherhood-allied Wasat Party.
Speaking alongside a Brotherhood official and another Islamist politician, Mahsoub appeared to be sticking by the demand to reinstate Morsi by saying any solution must be on a "constitutional basis."
Presidential spokesman Ahmed el-Muslemani, when asked about initiatives on the table, said: "The ship has sailed and we have no way but to go forward."
Undeterred by the weekend's bloodshed, the Brotherhood gathered supporters for more rallies outside security facilities on Monday evening. They carried empty coffins as a symbol of their dead. Almost all the casualties in Saturday's all-out clash between protesters on the one side and police and some armed civilians on the other were pro-Morsi demonstrators.
The Interior Ministry has vowed to take decisive action against anyone who violates state property, raising fears of more bloodshed.
The Brotherhood called the Saturday clashes a "massacre." Human Rights Watch and field doctors interviewed by The Associated Press said many were killed by gunshots to the head and chest. The Interior Ministry said its policemen fired only tear gas, though witnesses say security forces also used live ammunition and birdshot.
Security officials said Monday that a police captain died of wounds after being hit in the eye with birdshot from protesters. The officials spoke on condition of anonymity because they were not authorized to brief reporters.
Ashton also met with members of grassroots youth-led protest groups such as April 6 and Tamarod, Arabic for "Rebel," a main organizer of the mass protests that led to the coup.
After meeting with Ashton, Mahmoud Badr of Tamarod said he asked her to condemn all armed sit-ins.
"We have no intention of going back one step ... They must break up these sit-ins and hand in their wanted leaders," he said. Arrest warrants have been issued against top Brotherhood leaders.