South Sudanese refugees walk at a border gate in Joda
South Sudanese refugees walk at a border gate in Joda, in the Jableen locality in Sudan's White Nile State, after arriving from the South Sudanese war zones of Malakal and al-Rank, January 16, 2014. REUTERS/Mohamed Nureldin Abdallah (SUDAN - Tags: CIVIL UNREST CONFLICT SOCIETY IMMIGRATION POLITICS)
South Sudanese refugees wait at a border gate in Joda
South Sudanese refugees wait at a border gate in Joda, in the Jableen locality in Sudan's White Nile State, after arriving from the South Sudanese war zones of Malakal and al-Rank, January 16, 2014. REUTERS/Mohamed Nureldin Abdallah (SUDAN - Tags: CIVIL UNREST CONFLICT SOCIETY IMMIGRATION POLITICS)
South Sudanese refugees wait at a border gate in Jod
South Sudanese refugees wait at a border gate in Joda, in the Jableen locality in Sudan's White Nile State, after arriving from the South Sudanese war zones of Malakal and al-Rank, January 16, 2014. REUTERS/Mohamed Nureldin Abdallah (SUDAN - Tags: CIVIL UNREST CONFLICT SOCIETY IMMIGRATION POLITICS)
South Sudanese refugee walk at a border gate in Joda
South Sudanese refugee walk at a border gate in Joda, in the Jableen locality in Sudan's White Nile State, after arriving from the South Sudanese war zones of Malakal and al-Rank, January 16, 2014. REUTERS/Mohamed Nureldin Abdallah (SUDAN - Tags: CIVIL UNREST CONFLICT SOCIETY IMMIGRATION POLITICS)
A Sudanese official registers South Sudanese refugees at a border gate in Joda
A Sudanese official registers South Sudanese refugees at a border gate in Joda, in Sudan's White Nile State, after they arrived from the South Sudanese war zones of Malakal and al-Rank, January 16, 2014. REUTERS/Mohamed Nureldin Abdallah (SUDAN - Tags: CIVIL UNREST CONFLICT SOCIETY IMMIGRATION POLITICS)
South Sudanese refugees wait at a border gate in Joda
South Sudanese refugees wait at a border gate in Joda, in the Jableen locality in Sudan's White Nile State, after arriving from the South Sudanese war zones of Malakal and al-Rank, January 16, 2014. REUTERS/Mohamed Nureldin Abdallah (SUDAN - Tags: CIVIL UNREST CONFLICT SOCIETY IMMIGRATION POLITICS)
A South Sudanese refugee drinks water after arriving at a border gate in Joda
A South Sudanese refugee drinks water after arriving at a border gate in Joda, in the Jableen locality in Sudan's White Nile State, after arriving from the South Sudanese war zones of Malakal and al-Rank, January 16, 2014. REUTERS/Mohamed Nureldin Abdallah (SUDAN - Tags: CIVIL UNREST CONFLICT SOCIETY IMMIGRATION POLITICS)
South Sudanese refugees wait at a border gate in Joda in Sudan's White Nile State
South Sudanese refugees wait at a border gate in Joda, in the Jableen locality in Sudan's White Nile State, after arriving from the South Sudanese war zones of Malakal and al-Rank January 16, 2013. REUTERS/Mohamed Nureldin Abdallah (SUDAN - Tags: CIVIL UNREST CONFLICT SOCIETY IMMIGRATION POLITICS)
South Sudanese refugees wait at border gate in Joda, in Jableen locality in Sudan's White Nile State
South Sudanese refugees wait at a border gate in Joda, in the Jableen locality in Sudan's White Nile State, after arriving from the South Sudanese war zones of Malakal and al-Rank, January 16, 2014. REUTERS/Mohamed Nureldin Abdallah (SUDAN - Tags: CIVIL UNREST CONFLICT SOCIETY IMMIGRATION POLITICS)
South Sudanese refugees wait at border gate in Joda, in Jableen locality in Sudan's White Nile State
South Sudanese refugees wait at a border gate in Joda, in the Jableen locality in Sudan's White Nile State, after arriving from the South Sudanese war zones of Malakal and al-Rank, January 16, 2014. REUTERS/Mohamed Nureldin Abdallah (SUDAN - Tags: CIVIL UNREST POLITICS SOCIETY IMMIGRATION CONFLICT)