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LONDON, Jan 18 (Reuters) - Britain's tourism boom since Brexit vote faded in the three months to September as growth in the number of visitors slid to a one-year low, official data showed on Thursday.
Tourism has been a winner from the 2016 Brexit vote which pushed down the value of the pound, making Britain a more attractive holiday destination for foreign tourists and encouraging British holidaymakers to stay at home.
The number of overseas visitors to Britain rose by 2.7 percent year-on-year in the third quarter of 2017, the weakest increase in a year and following an 8.9 percent rise in the second quarter, the Office for National Statistics (ONS) said.
Nonetheless, the continued growth in tourism was a factor behind Britain's faster economic growth in the third quarter, said economist Howard Archer from EY ITEM Club consultancy.
Thursday's figures also showed the number of Britons traveling abroad fell by 0.4 percent year-on-year during the third quarter, the first drop since early 2013.
The world's sixth-biggest economy largely withstood the immediate shock of the referendum decision in 2016 to leave the EU. It felt more of an impact in 2017 due to higher inflation - caused by a fall in the value of the pound - and uncertainty among businesses about what Brexit means for them.
Tourism, however, has been a bright spot.
Thursday's data suggested currency moves were a big factor behind trips to Britain.
The number of visitors from North America fell 5.4 percent year-on-year in the third quarter, weighed by the U.S. dollar weakening almost 8 percent against the British pound during the first nine months of 2017, after sterling's slump in 2016.
By contrast, visits from the European Union were up 3.5 percent, likely boosted by the euro strengthening by almost 4 percent against the pound between January and September 2017.
Spending by foreign visitors in Britain rose by 7.7 percent in the third quarter, the smallest annual increase since the end of 2016.
Spending from North American and European visitors decreased. But travelers from the Middle East, China, Israel and South Africa ramped up their purchases.
The ONS said there was high spending recorded by visitors from Saudi Arabia in particular, although it cautioned that sample sizes for this were relatively small. (Reporting by Andy Bruce; Editing by William Schomberg and Alison Williams)