Khartoum (AFP) - The United Nations warned on Wednesday civilians are bearing the brunt of ongoing fighting in Sudan's Blue Nile state amid reports thousands of people have been displaced since early May.
President Omar al-Bashir has been battling the Sudan People's Liberation Army-North (SPLA-N) in the Blue Nile and nearby South Kordofan regions since 2011.
There have been reports that fighting in Blue Nile's Bau district displaced thousands of people in May.
"As conflict has increased in Blue Nile, it continues to be civilians who bear the brunt of this fighting," said Geert Cappelaere, the interim UN resident and humanitarian coordinator in Sudan.
"Humanitarian needs are rapidly rising in Blue Nile, but aid agencies are often not permitted to independently assess humanitarian needs and respond accordingly in the state," he said in a statement.
Access to Blue Nile is tightly controlled and it is difficult to check reports of fighting but officials there have said thousands of people fled their homes in May.
"According to the Humanitarian Aid Commission (HAC) in Blue Nile, around 11,000 people have been displaced by fighting in Bau district since early May," said Damian Rance, of the UN's Office for the Coordination of Humanitarian Affairs.
The UN had been unable to independently verify the figure from the government-run HAC, Rance said.
The SPLA-N could not be reached for comment but the Sudanese military denied there had been major fighting in Blue Nile in May.
"All that we have in the state is just some small insecurity in the southwest, and this does not include Bau locality," Colonel Al-Sawarmy Khaled Saad told AFP.
The SPLA-N mounted a campaign against the Khartoum government in 2011, complaining they were being marginalised.
Khartoum has also been facing insurgents in the western Darfur region since 2003, where 2.5 million people have been displaced.
Bashir is wanted by the International Criminal Court for alleged war crimes in Darfur.