Just six weeks after he returned to the job, Sudan's Prime Minister Abdalla Hamdok announced on Sunday he was stepping down.
Hamdok was ousted from power in October in a military coup, only to be reinstated a month later in a controversial deal with the military.
He has since failed to name a government as protests have continued against the army.
In a televised address, Hamdok said he had tried in vain to forge a consensus between deeply divided factions.
"Based on everything I have mentioned, I decided to give back the responsibility and announce my resignation as prime minister to give a chance to another man or woman of this noble country to continue leading our dear nation and help it pass through what's left of the transitional period to a civilian democratic country."
Hours before his speech, security forces fired tear gas at demonstrators in Khartoum as they marched towards the presidential palace.
At least three of the protesters were killed, according to a doctors' committee aligned with the movement.
The demonstrators want the military to play no role in government and demand a transition to free elections.
Hamdok's resignation throws the country's political future even deeper into uncertainty.
He became leader three years ago under a power-sharing agreement between the military and civilians following the overthrow of long-time leader Omar al-Bashir.