South Sudan's President Salva Kiir has signed a power-sharing agreement with rebel leader Riek Machar and other opposition groups in a bid to end five years of civil war.

Large crowds cheered outside the venue in Sudan's capital, Khartoum, as the deal was signed.

Since the war broke out in 2013, about four million people have been displaced.

Analysts say there's still great concern about whether this new agreement will succeed.

Dr James Okuk has been speaking to the BBC's Newsday programme about the deal.