The Electoral Commission has Monday nominated former army commander Maj Gen Mugisha Muntu.
Muntu is now officially the presidential candidate for Alliance for National Transformation (ANT) party.
He was later given a car and security detail to aid his campaign trail.
Speaking after the nomination, Muntu said he aims to give back Ugandans their dignity.
He said the struggle to remove Museveni from power has officially started today.
He called upon those who have lost hope to regain their vigour and struggle for change.