Destinations struggling to attract visitors after terrorist attacks will continue to see a fall in international arrivals, flight bookings suggest.

Turkey will be hardest hit, with bookings for September to December expected to be down by 52% on the same period last year.

Bookings to France are down by nearly 20% over the same period. Research also suggests Spain, Portugal and Italy are the favoured substitute destinations in southern Europe.

Travel data company Forward Keys analysed flight reservation data for Radio 4’s You and Yours programme.

Available seats to Spain from the UK increased by 19% in the first seven months of the year compared with the same period in 2015, Germany rose by 12%, and Portugal by 12%.

Low cost carriers are the airlines most responsible for pushing up capacity.

The series of terror attacks in France, starting with the Charlie Hebdo shooting, triggered a decreasing trend in international arrivals there, which was worsened by the Paris shootings in November 2015, according to Forward Keys.

France has suffered an accumulated year-on-year decrease of 5.4% between August 2015 and July 2016 and Paris suffered a worse decline, down 7.5% over the same period.

Bookings to Turkey were down by 15% between August 2015 and July 2016 compared with the same period a year earlier due to a series of terror attacks and July’s attempted coup d’etat.

Forward Keys co-founder and chief executive, Olivier Jager, said: “Travellers create a situation when they decide to visit alternative destinations.

“Operators and airlines decide to use their aircraft for other routes that allow them to fill their planes.”

International arrivals into Tunisia fell by 39.4% between August 2014 and July 2015, when a series of terror attacks – including the beach massacre in Sousse – targeted tourism destinations in the country.

However, figures from the Tunisian Tourist Board show that there has been an increase in the number of visitors from Algeria and Russia.

The number of Russian tourists visiting Tunisia has more than doubled from 63,054 to 131,434 in the period between July 2014 and July 2016. The number of Algerian tourists has tripled from 65,000 in 2014 to 194,370 over the same period.

Data collated by Forward Keys suggests international arrivals for the coming quarter are up by 13% compared with the equivalent period last year.

Jager said: “We see a slight improvement in terms of bookings, which have increased by 13% for the period September to December.

Turkey is predicted to suffer the hardest with bookings for September to December this year expected to be down by 52% compared with the same period in 2015 – while reservations to France are down by around 20% for the same period.