Sudan's President Omar al-Bashir says there will be no further talks with South Sudan, defying international calls for the countries to settle their differences through dialogue.

Mr. Bashir made the comments to soldiers Monday during a visit to the oil-producing area of Heglig, which the Sudanese army regained from southern forces on Friday.

Mr. Bashir said the south only understands the language of “guns and ammunition.”

Meanwhile, officials and witnesses in South Sudan say Sudanese warplanes bombed inside the south's Unity state on Monday, killing at least three people, including one boy. The bombs struck in and around the border town of Bentiu.

The deputy head of South Sudan's military intelligence called the bombings near Bentiu a “serious escalation” and a “clear provocation.”

The United States on Monday condemned what it termed Sudan's military incursion. State Department spokeswoman Victoria Nuland said the U.S. recognizes the south's right to self-defense, but urged Juba to “exercise restraint” in its response to the bombardments.

The European Union also restated its call for both sides to end the fighting and resume talks.

The two sides have given conflicting reports of casualties during the battle for Heglig, with Sudan saying 400 South Sudanese troops were killed and South Sudan saying the number is a fraction of what Sudan claims.

Sudan says it made an orderly and voluntary pullout from Heglig, following international pressure to withdraw. Sudan says it retook the area by force.

The two countries have been unable to resolve disputes over borders, oil and citizenship stemming from the south's independence last July.

The north and south previously fought a 21-year civil war that killed more than two million people. The war ended with a 2005 peace agreement that included an independence referendum for the south.