One of Ethiopia's main opposition parties, The Oromo Federalist Congress (OFC), has announced its withdrawal from parliamentary election scheduled for June until its demands are met.

It wants its jailed leaders to be released and its offices across Oromia state to be allowed to operate.

Senior members of the party Bekele Gerba, Dejene Tafa and Jawar Mohammed are facing terrorism charges.

They were charged in September in relation to a wave of ethnic unrest that followed the murder in June of popular musician Hachalu Hundessa.

“If our questions are answered and our demands are met, we will remain in the race [election],” party official Tiruneh Gemta told the BBC.

The authorities have not yet commented on the party's withdrawal.

Another opposition party, The Oromo Liberation Front (OLF), is also mulling withdrawing from the election citing imprisonment of its senior leaders and closure of its offices - including the head office in the capital, Addis Ababa.

The withdrawal of the two main parties could undermine the credibility of the election.