The French commander of a European Union peacekeeping force which had been due to deploy in the Central African Republic this week said Wednesday he did not have enough soldiers.

"The deployment hinges on the creation of a logistical unit of around 100 forces," General Philippe Ponties told French radio RFI, describing the shortage of volunteers as "worrying".

Former colonial power France sent troops to Bangui in December in a bid to stem a cycle of ethnic and religious killing the world feared could evolve into genocide.

Stopping the violence has proved more difficult than expected however and France has already once extended the mandate of its mission but received little support from European partners

Brussels last month approved the creation of a European Union peacekeeping force of 800 to 1,000 troops to help the French and African Union forces.

"Consultations are under way with all member states and I have not lost hope of finding a solution that will eventually allow to recommend deployment," he said.

But troop contributing nations have not rushed to the call and, with all eyes now on the crisis in Ukraine, observers argue that is unlikely to change.

The nation contributing the largest number of troops with 150, Georgia, is not even a member of the bloc.

The others are France -- which already has 2,000 troops on the ground as part of its unilateral Sangaris operation -- Estonia, Latvia, Spain, Poland and Portugal.

"One last push is needed to allow for a deployment. It isn't much but it is essential and we are eagerly awaiting it," said Ponties on RFI, urging EU states to honour their pledges.

"Given the current security and humanitarian situation in the Central African Republic, I think our deployment is a somewhat urgent matter," he said.

The chronically unstable country sank into chaos when rebels who had helped topple president Francois Bozize a year ago went rogue.

The ensuing campaign of killing, raping and looting by the mainly Muslim former rebels prompted members of the Christian majority to form vigilantes.

The new internationally-backed government, French and African Union forces have struggled to break the cycle of revenge attacks, which has forced nearly a quarter of the country's population of 4.6 million from their homes.