Darfur rebel forces gather as they guard during the visit of Joint Special Representative (JSR) Ibrahim Gambari at Fanga Suk village, in East Jebel Marra (West Darfur), 88 km from Tawilla March 18, 2011 (Reuters)

The U.S. State Department released a statement on Thursday, urging the world’s youngest nation to immediately comply.

“The United States calls on the Government of the Republic of South Sudan to comply with its commitments to cease harboring or providing support for Sudanese armed opposition groups, as required by UN Security Council Resolution 2046 (2012). Despite its obligations under international law and repeated agreements between the Government of the Republic of South Sudan and the Government of Sudan to end such support, credible reports continue to indicate the Government of the Republic of South Sudan is harboring and providing assistance to armed Sudanese opposition groups,” partly reads the strongly worded statement issued by Mark C. Toner, Deputy Department Spokesperson.

The statement urged President Salva Kiir’s government to redouble their efforts to meet the commitments they recently reached with Sudan under which both sides agreed to end support for armed opposition groups on either side.

U.S. said it has got evidence that Juba is still harbouring and supporting the Sudanese rebels fighting to overthrow President Bashir in Khartoum.

Washington has also accused the Sudanese rebels of interfering in the internal conflict in South Sudan by fighting alongside President Kiir against opposition group led by former First Vice President, Riek Machar.

“The presence of Sudanese armed opposition forces in South Sudan, and their involvement in South Sudan’s internal conflicts, destabilizes both Sudan and South Sudan. It is, moreover, a violation of the terms of the Agreement for the Resolution of the Conflict in the Republic of South Sudan,” said the statement.

“We call on the Government of the Republic of South Sudan to ensure Sudanese armed opposition groups are not in a position to conduct armed operations within South Sudan or across the border in Sudan.”

Washington also urged both Sudan and South Sudan to fully respect the 2012 Agreement on Security Arrangements, and withdraw their armed forces from the Safe Demilitarized Border Zone.

The two countries have been trading accusations that either side was supporting rebels against the other.