Monsignor Dieudonné Nzapalainga leans forward, frowning. His bulky frame fills the hotel armchair as the latest news agency copy is read to him. "That's bad. Very bad," he says quietly. The Reuters reports describes a convoy of more than two dozen vehicles carrying heavily armed Seleka rebels leaving Bangui, the capital of the Central African Republic (CAR), and heading north.

The news fills the city's archbishop with gloom. "They needed to be held accountable for what they had done. We cannot have impunity," he says wearily. His friend and companion on this London visit, the imam Oumar Kobine Layama, representing the country's Muslim minority, nods in agreement.

The Central African Republic descended into chaos in March last year, when the mainly Muslim Seleka rebels ousted President François Bozizé. Archbishop Nzapalainga appealed for help from the international community on the Global development site in November, warning that the country was teetering on the edge of catastrophe. Then 65,000 had fled from their homes. Today the total is nearer 1 million, almost a quarter of the population.

The archbishop and the imam have been touring European capitals, seeking support for their benighted country. In France they met President François Hollande; in London they are being received by Lady Warsi and a handful of officials.

The religious leaders are appealing to the British government for political support to try to halt the killings. "In particular," their letter to the prime minister, David Cameron, reads, "we call on the United Kingdom to support EU efforts in a full deployment of Eufor" – the European rapid reaction force.

The UN has warned repeatedly of the danger of a full-scale genocide in CAR. Nzapalainga says this is a real threat, with Christian and Muslim youths roaming the streets, seeking revenge for previous atrocities. "The two groups are at war," warns Kobine. "And they are led by bandits."

Has the presence of 1,600 French and 4,000 African forces done anything to improve the situation? Yes, both men agree. "If it was not for them the whole country would have been in flames," the archbishop says.

But the situation is complex. Chadian forces are among the African troops who comprise the bulk of the peacekeepers in and around Bangui. They have been closely allied with the Seleka and have been accused of joining them in attacks on Christian communities.

The archbishop and the imam fear the rebels will re-form in the remote north-east and reopen their campaign. They say 10 generals who led the rebellion came from Chad, although they describe them as mercenaries rather than Chadian army officers. But both agree that Chad and Sudan have repeatedly intervened in CAR's affairs. "We have a soft belly," says Nzapalainga. "Everyone takes advantage of us."

A Christian militiaman carrying a machete walks past French soldiers in Bangui

The real problem is that, seen from Paris, CAR is of only secondary importance compared with Chad. France has had a particular penchant for the Chadians since the former colony came out in support of General de Gaulle during the second world war. A French military base is situated in eastern Chad, with troops ready to serve across Africa.

But the religious leaders remain hopeful that the situation can be salvaged. A week ago, Catherine Samba-Panza, a respected businesswoman with a reputation for independence, was elected to serve as head of state by the transitional parliament. She is the country's first woman president and the archbishop warns she will not succeed without international support. "Civil servants have not been paid for the last five months," he says. "The army needs to be rebuilt so that we can protect ourselves."

Clearly there is much to be done, but the omens are not all bad. The US is threatening sanctions against those involved in religious-based violence. Germany, for the first time in years, is contemplating sending troops into an African conflict. The defence minister, Ursula von der Leyen, said on Sunday her country could not "look the other way when murder and rape are a daily occurrence, if only for humanitarian reasons". Even Britain, which has ruled out providing ground troops, is willing to provide financial and political support to these endeavours.

Ending the violence will require international as well as African resolve, particularly if Chadian and Sudanese interference in the Central African Republic is to be ended. But it will also need goodwill among the Christian and Muslim communities. "We are doing what we can," Kobine says. "We have trained 30 religious leaders on dialogue and conflict resolution. Now we must train many more."

It is a small beginning in a vast and troubled land, but the first seeds of peace must be planted somewhere and the archbishop and the imam are doing what they can.