U.S. Secretary of State Hillary Clinton urged South Sudan and Sudan on Friday to end an oil dispute that has brought the neighbours to the brink of war, during the highest-level visit of a U.S. official to Juba since its independence a year ago.

Clinton began her first visit to Africa's newest nation just

hours after a U.N. Security Council deadline expired for the neighbours to solve a long list of disputes ranging from border security to oil payments.

The two nations came to the brink of a full war in April after border fighting escalated, the worst violence since South Sudan became independent in July last year under a 2005 agreement that ended decades of civil war with Khartoum.

The messy divorce failed to clarify where the border lay and

how much landlocked South Sudan should pay to export its oil through the north. Oil is the lifeline of both economies.

Clinton said the two nations should reach an oil agreement as a first step to ending hostilities. Juba sent both economies into turmoil when it shut down its oil output in January to stop Khartoum seizing oil for what the latter called unpaid fees.

"This is a delicate moment...Now we need to get those (oil) resources flowing again," Clinton told reporters after meeting South Sudanese President Salva Kiir for more than one hour in his office, where she hugged him upon arrival.

Reuters