BBC News with Jonathan Izard

President Barack Obama has welcomed the successful completion of voting on the first day of southern Sudan's referendum on independence. He said it was a historic step toward implementing the comprehensive peace deal that ended the war between north and south in 2005, and the United States was fully committed to helping the new African state expected to be approved by the vote. A big

turnout

was reported at polling stations across southern Sudan. Southerners in the north also voted, but the mood there was more

subdue

d. A senior official from President Omar al-Bashir's National Congress Party, Ibrahim Ghandour, says separation is an

inevitable

consequence of the peace deal known as the CPA.

"The separation of the south if it occurs following the referendum, it was a price for an achievement of peace. When we were signing the CPA, we were between a choice of two - we either remain in one united country where its people are fighting, or accept an idea of self-determination at the price of peace."

An Iranian passenger plane has crashed in the northwest of the country with more than 100 people on board. Reports say the site of the crash has been difficult for emergency workers to reach because of heavy snow. Maddy Savage reports.

According to the semi-official news agency Fars, the Iran Air plane took off from the Iranian capital Tehran and was flying near the city of Urumiyeh in the northwest of the country when it crashed. Reports on Iranian state television suggest that the plane