(Updates top, adds British Ambassador summoned)
By Khalid Abdelaziz
KHARTOUM, June 12 (Reuters) - The top U.S. diplomat for Africa is joining an international push to press Sudan's military rulers and the opposition towards a deal on a transition to democracy two months after the overthrow of former President Omar al-Bashir.
The military and opposition groups have agreed to resume talks on the formation of a transitional council that collapsed after the violent dispersal of a protest sit-in on June 3, an Ethiopian envoy has said.
The bloodshed has drawn expressions of concern from world powers including the United States, which imposed sanctions on Sudan under Bashir over its alleged support for militant groups and the civil war in Darfur.
Tibor Nagy, the U.S. assistant secretary of state for Africa, met the opposition, an opposition leader said, after he held talks with Sudan's acting deputy foreign minister Ilham Ibrahim.
"He will call for a cessation of attacks against civilians and urge parties to work toward creating an enabling environment ... for talks to resume," the State Department said.
The United States also named veteran diplomat Donald Booth as its envoy to Sudan on Wednesday.
Stability in the nation of 40 million is crucial for a volatile region struggling with conflict and insurgencies from the Horn of Africa to Egypt and Libya.
The military council has been bolstered by support from Saudi Arabia and the United Arab Emirates, which between them have offered $3 billion in aid.
"The current detente in Sudan calls for optimism and we call for the establishment of an agreement that will drive the transitional phase through a real and stable partnership," UAE Minister of State for Foreign Affairs Anwar Gargash said on Twitter.
He also praised the role of Ethiopian Prime Minister Abiy Ahmed, who flew to Khartoum last week on a mediation mission and is expected to return this week.
The crackdown from June 3 led to at least 118 deaths, according to opposition-linked medics. The government has confirmed 61 deaths, including three security personnel.
Sudan's Foreign Ministry summoned the British ambassador in Khartoum to protest at his remarks on political developments in the country, SUNA reported.
Britain's ambassador Irfan Siddiq tweeted last week as authorities tried to disperse the main protest site: "No excuse for any such attack. This. Must. Stop. Now."
Talks between the military and the opposition were already deadlocked before the crackdown as the two sides struggled to agree on the make-up of a sovereign council that will oversee the transition.
In Khartoum, employees returned to work on Wednesday and store owners opened their shops, after the alliance of protesters and opposition groups suspended a three-day campaign of strikes and civil disobedience.
Many people lined up outside ATMs and banks that had closed first for the Eid holiday at the start of June and then because of the strike.
Sudan is still suffering an internet outage. Some side streets that had been closed by protesters were still partially blocked by remnants of barricades. Rubbish bins not emptied for days were overflowing. (Additional reporting by Sylvia Westall in Dubai and Nayera Abdallah in Cairo; Writing by Lena Masri and Nadine Awadalla; Editing by Alison Williams)