BRUSSELS, Belgium -- European Union foreign ministers on Monday unanimously approved a joint military force to assist French and African troops trying to quell anarchy and bloodshed in Central African Republic.

The 28-nation bloc is now preparing operational details to dispatch about 500 soldiers to stabilize the situation in and around the country's capital, Bangui, said French Foreign Minister Laurent Fabius.

However, it is still mostly unclear which nations will contribute soldiers to the EU mission.

The deployment initially limited to six months would come as reinforcement to some 1,600 French troops that were quickly dispatched there last month to assist some 4,400 overwhelmed African Union troops to restore order.

EU countries will hold another vote to approve the deployment once the operational details have been hammered out. Officials hope the mission can be on the ground by March.

International donors holding a separate meeting in Brussels, meanwhile, pledged $496 million in humanitarian assistance for the strife-torn country, U.N. humanitarian chief Valerie Amos announced.

"We have a 100-day-plan which is now fully funded and now additional resources which will go toward the plan for the rest of the year," she said.

CAR started descending into chaos last March with a rebel force's bid to overthrow longtime President Francois Bozize. The fighters soon began pillaging homes and killing civilians. Over time, resentment grew in the predominantly Christian country toward the rebels, most of them minority Muslims from the distant north, setting the stage for increasing sectarian violence.

More than 1,000 people were killed over the course of several days in Bangui last month alone, and nearly 1 million people have been displaced from their homes.

"The brutality, violence and sectarian nature of the crisis concern us all," Amos insisted.

As part of the new humanitarian assistance, some $200 million is earmarked for immediate humanitarian needs, with the remainder set aside for financing medium-term projects to help the country get back on its feet, EU Commissioner Kristalina Georgieva said.

The Commission, the European Union's executive arm, is contributing some $60 million. The U.S. gives $45 million, France about the same, the World Bank around $100 million and the African Development Bank another $75 million, according to the EU Commission.

At the foreign ministers' meeting, Estonia offered up to 55 service members and Lithuania, Slovenia and Finland said they were considering whether to participate, according to EU officials. Greece offered to host the force headquarters.

French President Francois Hollande previously said Poland has offered a transport plane and the personnel to fly and maintain it.

"Within its zone of operations, the military force will contribute to the regional and international efforts to protect the most-endangered people and increase the civilians' freedom of movement," the ministers said in their joint statement.

Krista Larson in Dakar, Senegal, contributed reporting.