With the new constitution of 30 November 1975, PRPB became the sole legal party in the country.

[1] Ideologically, the party stated it was committed to Marxism–Leninism, although in practice was broadly nationalist.

[2][3] In the parliamentary elections of 1979, 1984 and 1989, PRPB was the only party contesting.

[4][5] In 1989, the party renounced Marxism–Leninism as its official ideological guidance.

[6] The party then dissolved and succeeded by the Union of Forces of Progress.