The Burkinabe parliament on Monday granted amnesty to President Blaise Compaore, who came to power in a 1987 coup, and to his predecessors in the top job.

The immunity from prosecution covers all heads of state since Burkina Faso gained independence from France in 1960.

It will affect former leaders Saye Zerbo, in power from 1980-82, and Jean-Baptiste Ouedraogo, who served from 1982-83, as well as to the 60-year-old Compaore. All three came to power following coups.

Among other measures adopted by the deputies was the introduction next year of a "moderating" upper house Senate, said Jerome Bougouma, the minister for territorial administration.

The parliament also decided to set upper and lower age limits for presidential candidates -- they can be from 35 to 75 years old.

The opposition boycotted the vote, arguing that the reforms are devised "mainly to help President Blaise Compaore to maintain power."

The constitutional reforms were proposed last year by a consultative council put together by Compaore after popular protests and mutinies against his regime sprang up.

The rural country is one of the poorest in the world, with nearly half of its 16 million population living in poverty.

Protests first broke out in February over high food prices, unemployment, rising costs and looting by troops. Soldiers and paramilitary police joined in in April, going on the rampage in several towns.

The political reform group did not agree to a proposal to allow Compaore to seek a fresh mandate in 2015.

That idea, backed by his party, faces wide opposition in the impoverished west African nation.