BERLIN - They may not have qualified for the tournament, but travellers from the United States are among those most gripped by World Cup fever in terms of flight bookings to Russia, with bookings up 66 percent, data showed on Tuesday.

Less surprisingly, the biggest fall in bookings, a drop of 16 percent, is from Italy, which failed to qualify for the World Cup for the first time in its history, travel technology company Travelport said.

Overall, flight bookings to Russia from the United States for travel during the tournament from June 14 to July 15 have risen 136,503 in volume, an increase of 34 percent, according to Travelport's analysis of data from the major global distribution systems (GDS).

Bookings from the United States are up by 13,654 in volume, an increase of 66 percent, while Germany accounts for the largest growth in booking volumes of 16,213, an increase of 44 percent.

"It's great to see the World Cup is encouraging people to travel," Travelport Chief Commercial Officer Stephen Shurrock said. "German supporters are clearly feeling optimistic they can retain the title with the highest total number of fans travelling to watch their team,"

The U.S. interest is also backed up by separate data from ForwardKeys released last week, which analysed data from the GDS along with some airlines and tour operators but which looked at arrivals from June 4 to July 15.

According to that analysis, the United States is responsible for the greatest number of additional visitors to Russia, although ForwardKeys highlighted that the United States has a sizeable Latin American population, traditionally among the biggest soccer fans.

"This result may seem surprising because the USA has not qualified for the finals but interest in the spot has grown strongly since the 1994 World Cup when it was the host nation," ForwardKeys said.

(Reporting by Victoria Bryan, editing by Louise Heavens) ((victoria.bryan@thomsonreuters.com; +49 30 2888 5169; Reuters Messaging: victoria.bryan.thomsonreuters.com@reuters.net Twitter:@vl_bryan))