PARIS (AFP) - A French Roman Catholic priest abducted in Cameroon by Islamic militants arrived home on Wednesday after a seven-week ordeal he described as a time of "terrible boredom, sadness and anger."

Mr Georges Vandenbeusch, who was freed on Tuesday, touched down at the military air base of Villacoublay near Paris, where President Francois Hollande greeted him and hailed his "courage" and "self-sacrifice".

The 42-year-old was kidnapped on Nov 13 by heavily armed men who burst into his parish at night in the far north of the central African country and reportedly took him to neighbouring Nigeria.

The radical Islamist movement Boko Haram, which has killed thousands of people in attacks against Christians and government targets in northern Nigeria, claimed responsibility for holding him soon after he was kidnapped.

The circumstances of his release are as yet unclear, but both France - often accused of paying ransoms for hostages despite stiff government denials - and Boko Haram have denied that a ransom was paid.

A source within the Islamist group told AFP on Wednesday they had asked Paris for money through the Cameroon government, but the French government refused and requested Mr Vandenbeusch be released on humanitarian grounds because of his status as a clergyman.

"The leadership (of Boko Haram) decided to release the priest on compassionate grounds and having benefited from his medical expertise," the source told AFP.

"The priest offered medical service to sick members during his period of captivity. The leadership felt there was no longer need for keeping him." Speaking in the Cameroonian capital Yaounde before he boarded a flight back to France, Mr Vandenbeusch said he had not been mistreated by his captors despite being kept in "rustic conditions".

He expressed "great joy" at returning home but said people should remember those who are still being held hostage.

Mr Vandenbeusch described his time in captivity as a period of "terrible boredom, sadness and anger because I'm very fond of the parish where I worked" in Cameroon.

"I was under a tree for a month and a half," he said, explaining that his two main guards spoke a local language and not English, he did not have anything to read, or a radio to listen to.

Speaking at the air base on Wednesday morning, Hollande warned other Frenchmen and women in high-risk areas to take care and avoid putting themselves in danger's way.

"We have to warn those who may be at risk in areas where there is danger," said Mr Hollande.

He said this applied not only to "priests who have a mission to accomplish" but to other French nationals.

France needed to be "rigorous" not to allow other hostages to be taken, added mr Hollande.