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By James Regan and Michelle Nichols
PARIS/UNITED NATIONS, Feb 14 (Reuters) - France said on Friday it plans to send another 400 troops to help combat a crisis in the Central African Republic as U.N. chief Ban Ki-moon pleaded for more swift, robust international help to stop sectarian violence that could turn into a genocide.
French President Francois Hollande's office urged other countries to show "increased solidarity" and called on the United Nations Security Council to approve the creation of a U.N. peacekeeping force in the landlocked former French colony.
Some 838,000 people have been displaced since the mostly Muslim Seleka rebel group seized power in March last year in the majority Christian country. At least 2,000 people have been killed since December in what a U.N. official described as a wave of "ethnic-religious cleansing."
"The dark clouds of mass atrocities and sectarian cleansing loom over the Central African Republic," Ban told a U.N. Security Council meeting on cooperation between the world body and the European Union.
"We cannot claim to care about mass atrocity crimes and then shrink from what it means to actually prevent them," he said. "Our commitment to protect civilians is only as meaningful as the political, military and financial muscle deployed to defend them."
The additional troops will bring France's Central African Republic deployment to 2,000.
France sent 1,600 troops in December to help an African Union force of 6,000 peacekeepers, while the European Union has agreed to send around 500 troops.
Hollande's office said that some of the additional 400 French troops would be later transferred to the European force.
"It's essential that this European force can be swiftly deployed and that member states of the EU can mobilize to contribute towards this," French U.N. Ambassador Gerard Araud told the Security Council.
"We are at a crucial stage in managing the Central African crisis. We avoided the worst but still we need to put an end to the cycle of ethnic and religious violence and avoid the country falling back into chaos," he said.
EU FORCE "SOON"
At a "force generation" conference in Brussels on Thursday, six EU states offered "substantial" contributions of soldiers or police for Central African Republic, diplomats said, but those countries were not named.
"We have more than 500 troops. The force generation conference ... is, as my understanding, looking at double that number," European foreign policy chief Catherine Ashton told reporters after the Security Council meeting in New York. "I trust that the force will be on the ground very, very soon."
Estonia and non-EU member Georgia have already voiced readiness to offer troops, diplomats said.
Canada, Georgia, Norway, Serbia, Turkey and the United States, all non-EU countries, took part in Thursday's conference, diplomats said.
Russia voiced concern that some non-EU countries could be part of the European deployment to Central African Republic.
"We're concerned this might have an impact on the management of the EU mission in an already chaotic situation in the CAR," Russian U.N. Ambassador Vitaly Churkin said. "We won't hide that we're somewhat surprised ... there's still no clarity on precisely which countries will provide peacekeepers.
Ban is due to report to the U.N. Security Council shortly on options for transforming the current African Union peacekeeping force into a U.N. operation. He told the council in November that a U.N. force of up to 9,000 troops and 1,700 police could be needed for Central African Republic.
Ban said on Tuesday that he had asked France and other countries to consider sending more troops to the Central African Republic because the international response to the crisis "does not yet match the gravity of the situation." He said he was gravely concerned violence could spiral into genocide. (Aditional reporting by Adrian Croft; Writing by Michelle Nichols; Editing by Mark John, Toni Reinhold)