"We may have more to say about it next week," the senior French official said.

French officials said these groups had long been under surveillance.

French officials said that they had no knowledge of the group or whether it was involved in the attack.

"It is a question of how many times we have to pay the price," a French official said.

Three French officials involved in the decision resigned under pressure.

Many French officials hope she can be persuaded to stay.

French officials said the visit would take place this year, but they gave no date.

Only two tested positive for the disease, French officials said.

"Our position is very clear," a senior French official said.

French officials said such a center would be the first established there by Western nation.