South Sudan is accusing Sudan of bombing its border region Thursday despite a U.N. Security Council warning for the countries to end hostilities or face sanctions.

Southern army spokesman Philip Aguer told VOA that Sudanese warplanes dropped 12 bombs and launched artillery in the village of Lalop where southern forces are stationed.

Aguer said the attack, which took place at around 4 p.m. local time, was the first launched in the volatile border since Tuesday. The attack has not been independently confirmed.

The African Union says on Wednesday Sudan accepted “in principle” an AU roadmap for halting violence and resolving issues with South Sudan.

The roadmap gives the two countries 90 days to settle their issues or face binding international arbitration. The AU said South Sudan accepted the plan earlier this week.

The United Nations Security Council adopted a resolution Wednesday calling on the two countries to halt fighting and reach an agreement on oil, border and citizenship issues.

The African Union has said it is making arrangements for the “urgent resumption” of negotiations of all pending issues. Prior AU-mediated talks between the two Sudans have produced little progress.

South Sudan became independent from Sudan last July, six years after the end of a 21-year Sudanese civil war.