Government efforts to encourage Algerians to back constitutional reform have fallen flat, with fewer than one in four voting in Sunday’s referendum.
Turnout was 23.7%, a historic low for a major poll in Algeria.
It deals a blow to government hopes of satisfying the demands of a long-running protest movement with limited reform.
The proposed changes include a two-term limit for both the president and MPs.
But opposition parties - as well as the protest movement Hirak - had dismissed the plans as not going anywhere near far enough in transforming Algeria's political culture.