After reaching an agreement couple of weeks ago to share power over the transition period, the military in Sudan and the opposition groups have now signed a deal to that effect.
This was to put in place a transitional power-sharing body, comprised of military members and representatives from the pro-democracy coalition, known as the Forces for Freedom and Change.
The two sides have agreed to rotate control of the sovereign council - the top tier of power - for just over three years.
They also agreed to a rotating presidency that will see the first head of state appointed by the military for the initial 21 months then the FFC will appoint whom they choose to lead the country for the remaining 18 months before national elections.
"We want a stable homeland, because we have suffered a great deal", Amin said in a speech after the ceremony.
"Signing the agreement is a historic moment for the Sudanese nation and initiates a new era of partnership", Mohamed Hamdan Daqlu, the TMC's deputy chairman, said in a speech following the signing of the deal.
These talks are expected to address whether to grant "absolute immunity" to generals for violence against protesters.
The powers of the legislative council go to the council of ministers and sovereignty council until the transitional legislative council is formed.
Political analyst Khalid al-Faki thinks the accord is good for Sudan's future.
The military has said the sovereign council should be able to veto appointments to the Cabinet and Cabinet decisions, something the protesters fear would deprive it of any real power.
But the agreement was thrown into doubt when new disputes surfaced last week over the military council's demand for immunity for council members against prosecution.
The Communist Party said it and some other factions rejected the deal signed Wednesday because it did not include the immediate handover of power to civilians and did not provide for an worldwide investigation of the violence.
The deal was a culmination of marathon talks that continued for more than 13 hours at Corinthia Hotel in the capital Khartoum, under mediation of African Union (AU) and Ethiopian envoys.
The declaration also stipulates that the two parties must abide by the principles of democracy, human rights and the traditional values of the Sudanese people.
Tensions climaxed on 3 June when armed men in military fatigues stormed a longstanding protest camp in Khartoum, shooting and beating crowds of demonstrators in a pre-dawn raid. The U.S. Embassy in Khartoum welcomed the deal and encouraged both sides to "continue the same spirit of cooperation to conclude a constitutional decree".