Leaders of opposition parties in Sudan have called for a national conference to draft a system of government that represents all Sudanese.

One report says they were turned away when they tried to present a memorandum to President Omar Hassan al-Bashir at his palace.

The opposition leaders accused the government of allowing the Islamists -- who they describe as a minority party -- to impose their ideology on the whole country, with what they said were disastrous results.

Sudan is to re-introduce a multi-party system on the first of January, ten years after General Bashir seized power in a coup.

However, opposition parties say they won't register under the new constitution.