<br/>The main Opposition candidate in Sudan's first multi-party Presidential election for nearly 25 years, Yassir Arman says he is withdrawing. The Sudan People's Liberation Movement (SPLM) said Yassir Arman would not stand against President Omar al-Bashir.<br/><br/>SPLM, who are former rebels from the south, blamed the continuing conflict in the Darfur region and electoral irregularities for his withdrawal.<br/><br/>President Omar al-Bashir said he will cancel a promised referendum on independence for southern Sudan if the SPLM boycotts the poll.