Sudan President Omar al-Bashir has been ousted and arrested.
In a televised address, the country's Defence Minister Awad Mohamed Ahmed Ibn Auf said the leader has been arrested and kept in a safe place.
"The supreme committee decided to implement what was not in the mind of other people and for a transitional period of two years the armed forces will take power with the representation of the people to pave the way for the people," he said, announcing that an election will be held at the end of the period.
"For a long time, examining what's going on in the state and the corruption that is going on... the poor are poorer and the rich are still rich and there are no equal chances for the same people."
The Sudani airspace and border crossings will be closed for 24 hours until further notice, he said, adding that a state of emergency will be in place for three months.
Earlier, Sudan's National Intelligence and Security Service announced the release of all political prisoners across the country.
Thousands have been camping outside the army headquarters.
The Strait of Hormuz remains open to all shipping except vessels linked to "Iran's enemies", Iran's representative to the UN maritime agency was quoted as saying in Iranian media reports published on Sunday.
The Gulf Cooperation Council (GCC) has renewed its condemnation of continued Iranian attacks on member states, including the targeting of infrastructure and oil facilities, in flagrant violation of international law and a direct threat to regional security, stability and the safety of global energy supplies.
The Qatar Ministry of Interior has confirmed six people died during a helicopter crash into "regional waters" on Sunday - with search and rescue teams still searching for the body of the seventh and final crew member.
Japan could consider deploying its military for minesweeping in the Strait of Hormuz, a vital artery for global oil supplies, if a ceasefire is reached in the U.S.-Israeli war on Iran, Foreign Minister Toshimitsu Motegi said on Sunday.