KHARTOUM (Reuters) - Sudan will continue to allow only limited access to United Nations agencies and aid groups in two war-stricken border states, the foreign ministry said on Sunday, despite calls from the United States to allow more access to avert famine.

Fighting broke out between government forces and rebels in South Kordofan in June last year, shortly before South Sudan declared independence under a 2005 peace deal that ended decades of civil war. The conflict spread to Blue Nile in September.

Both states border South Sudan and are home to tens of thousands of fighters who battled Khartoum as part of the southern army during the civil war. Sudan accuses Juba of continuing to back the insurgents, which South Sudan denies.

"Regarding relief, delivery and distribution will be through the humanitarian aid commission and the Sudanese Red Crescent society," the Foreign Ministry said in a statement on Sunday.

U.N. agencies and aid groups have only been able to keep small teams of local staff on the ground since the conflict erupted. The government, citing security risks, has stopped aid workers from visiting areas where there has been fighting.

The Foreign Ministry said office managers will only be allowed in state capitals and must obtain permission.

The United States has pressed Khartoum to allow more humanitarian access to South Kordofan and Blue Nile, saying food security could deteriorate sharply by March if aid flows do not increase.

Sudan's ambassador to the United Nations dismissed the concerns on Tuesday, saying the situation in the two states was "normal.

The violence has already forced about 417,000 people to flee their homes, more than 80,000 of them to South Sudan, the United Nations estimates. Locals have faced air raids and sporadic ground fighting, according to rights groups and refugees.

(Reporting by Alexander Dziadosz; Editing by Sophie Hares)