Updated

Zimbabwe's parliament has begun discussing a new constitution that reduces some of the president's powers, demands political impartiality from his longtime loyalists in the police and military and paves the way for a peace and reconciliation commission to investigate charges of human rights and electoral abuses.

The 160-page draft constitution, completed after three years of bickering between hardliners and reformers during often bitter and violent nationwide canvassing, will be voted on in a national referendum in April, ahead of elections to end a shaky coalition formed after the last disputed, violent polls in 2008.

Regional mediators made a new constitution a key condition for fresh elections. Lawmakers will not be able to change the draft unless there is a last minute revolt against it in the legislature, experts said Wednesday.