Demand for Christmas trips to Paris has slumped following last month's Islamist militant attacks in the French capital, according to data from travel information firm ForwardKeys.

Overall, net bookings - calculated by taking new bookings and deducting cancellations - recovered in the week starting Nov. 23, compared to the week immediately following the Nov. 13 attacks, thanks to fewer cancellations.

New bookings, however, remain around 25 percent lower compared to last year, and Christmas demand has stagnated at pre-attack levels. There is a lack of new bookings from all major source countries, including Britain, Germany, Italy, Spain and the United States, Forward Keys said.

"Put another way, in a normal year bookings for Christmas would be accumulating well now but following the attacks, enthusiasm has been dented," CEO Olivier Jager said.

Travel companies are feeling the impact, with several airlines saying the numbers of travellers heading to France are down, although many expect the effect will be short-lived.

Didier Le Calvez, who is managing director of luxury hotel Le Bristol and heads the luxury section at hotel association UMIH, said earlier this week that high-end Paris hotels had only sold 40-50 percent of their rooms for the end-of-year festive period, whereas normally they would be 80-90 percent booked.

The CEO of AccorHotels has said the French hotel group is seeing fewer last-minute bookings for the second half of December compared with a year ago and that the impact will probably last three or four months.

The ForwardKeys database contains reservations handled by more than 200,000 online and offline travel agencies worldwide.