The leader of the Central African Republic on Thursday appealed to France and the United States for
military support, as he faces a rebel advance on the capital.
President Francois Bozize called on the "great powers" to help stop the rebels, who have over the past month captured key towns and mining areas and vowed to topple the government.
President Francois Hollande stressed that French troops were in the country only to protect French citizens, not to get involved in the CAR's internal affairs, adding that "those times are over."
The rebel coalition known as Seleka is made up of militia who were previously integrated in the army but defected, claiming the government has violated the terms of a 2007 peace deal.
Residents in the capital Bangui said the mood was "tense."
"I think people are very worried about what might happen," said Sylvain Groulx of aid group Medecins Sans Frontieres (MSF) in Bangui.
MSF warned that doctors and nurses had already fled conflict-torn areas and that health services, normally weak in the impoverished and landlocked country of 4.5 million, were suffering even more.
"It is extremely difficult for the population to get basic services, especially in these difficult times," Groulx told dpa by telephone. "There were very limited services already, and it just gets worse right now."
Foreigners in the capital have expressed concern over growing anti-European sentiment.
Hollande on Wednesday bolstered security at the French embassy after it was attacked by protesters demanding Paris move to stem the rebel advance.
Neighbouring Chad has sent 150 soldiers to try to fight the rebels.
A European peacekeeping force in the country has so far indicated it will not take sides in the conflict.
Bambari, the third largest city, located in the north, fell to the advancing rebel forces on Sunday, after key mining areas in the east came under the rebels' control in past weeks.