Exclusive: Ex-South Sudan rebel leader believes unity government won't be ready by May 12

South Sudan's ex-vice president and former rebel leader Riek Machar is pictured during an interview with Reuters in Rome, Italy, April 12, 2019. REUTERS/Yara Nardi.

ROME (Reuters) - The two sides of war-ravaged South Sudan will not be able to meet a May 12 deadline to form a unity government because key requirements of a peace deal have not been met, former rebel leader Riek Machar told Reuters on Friday.

Machar - who should regain his post as vice president under the deal - said the government and the rebels needed another six months before forming a unity government.