A refugee woman in Andalusia camp for internally displaced people from southern Sudan, some 30 kms south of the capital Khartoum, on January 11, 2012.
The United Nations High Commissioner for Refugees (UNHCR) has declared a surge of arrivals by the Sudanese refugees in an already over-crowded camp across the border in southern Sudan.
"There has been a steady increased influx due to the ongoing fighting in the border areas between Sudan and South Sudan,” UNHCR spokesperson Melissa Fleming said on Friday.
“We are expanding our operations in this area called Yida where the population has swollen to over 35,000. So it's really a new wave of arrivals,” she added.
Fleming warned that the new arrivals would bring about humanitarian and food insecurity and that the population of the Yida camp is feared to rise to 40,000 by the end of May.
The UNHCR spokesperson also expressed concerns about the safety of the refugees in the volatile border region, saying the Yida camp is dangerously close to the border, where Sudanese and Southern Sudan army forces have been in clashes for weeks.
The Geneva-based Agency has also been encouraging the camp residents to move into Southern Sudan to more established camps.
UNHCR says some 12,000 Sudanese refugees have also entered South Sudan's Upper Nile State since the weekend.
South Sudan is currently hosting more than 115,000 Sudanese refugees from the Nuba Mountains in Sudan, where they have endured bombardment from Sudanese warplanes and a crisis-level food shortage.
Another 32,500 have found shelter in western Ethiopia from Blue Nile.
Fighting between the Sudan and South Sudan erupted weeks ago along the border after several rounds of failed talks to resolve disputes over oil revenues, border demarcation and citizenship.
Sudan accuses South Sudan of supporting anti-government rebels operating in the Darfur region and the states of Blue Nile and South Kordofan.
However, South Sudan accuses the Sudanese army of launching air strikes and ground attacks on its territory over the past weeks, but Khartoum rejects the allegations.
South Sudan gained independence from Sudan in July 2011 as part of a 2005 peace treaty, which ended decades of war between the two countries. Despite the treaty, the African neighbors are still at loggerheads over oil revenues and border demarcation.