BEIJING - China will send a mission to observe the upcoming referendum in Sudan at the invitation of both the northern and southern parts of the African state, a Foreign Ministry spokesman said on Tuesday.

"China hopes the referendum will be held in an atmosphere of justice, freedom, transparency and peace," the spokesman Hong Lei said at a regular news briefing, urging all sides involved to strive for peace and stability in the country.

Stipulated by the Comprehensive Peace Agreement inked between north and south Sudan in January 2005, the southern Sudanese are expected to vote on Jan 9 to decide whether the region should remain united with the north or secede to establish an independent state.

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"China will work with the international community and continuously play a positive and constructive role in promoting peace, stability and development in Sudan and this region at large," he said.

Sudanese President Omar al-Bashir in a visit termed by local media as "historical" in southern Sudan on Tuesday, called for unity of the African country, only days before a referendum in the autonomous region.

Addressing a reception ceremony in Juba, the capital of southern Sudan, aired live by the state-run Sudan TV, the Sudanese president said unity would be the most ideal choice to be taken by the southern Sudanese in the upcoming referendum slated for Sunday.

Describing the referendum as "the last period in the implementation of the Comprehensive Peace Agreement (CPA)", al- Bashir noted that the federal government in Khartoum was ready to recognize the results of the referendum if true desire of the southern Sudanese people was expressed.

He reiterated his demand that the referendum should be held in a just, free and transparent atmosphere.

"We have agreed on the item of self-determination for southern Sudan after we have become convinced that unity could not be achieved by force. We still want unity, but if the southern Sudanese want to separate, then it is welcome," al-Bashir said.

"We will respect what the southerners would decide and we will be happy that we have achieved the comprehensive peace. We will not mourn in the north, but we will come to the south again to celebrate the establishment of the new state," al-Bashir added.

Xinhua