MasterCard's "Worldwide Index of Global Destination Cities" predicted that London will see 16.9 million people arrive by air compared with a million less for second place city Paris and airmiles ahead of New York at 13th place with 7.6 million arrivals.

The index also said that London, for the second year running, will attract the highest international visitor spend at $21.1 million, just ahead of New York at $19.4 million.

"London offers better value for money than New York," MasterCard Worldwide's global economic advisor Yuwa Hedrick-Wong told Reuters.

The queen's diamond jubilee saw London fill with visitors from abroad and around Britain for four days of celebrations at the start of June and the Olympics which will take place at venues in and around London from July 27 to August 12 is expected to pull in visitors from all over the planet.

"As our fantastic Diamond Jubilee celebrations demonstrated, London knows how to throw a party and, as we prepare to host the greatest Games the world has ever seen, it is no surprise our capital is the top choice for tourists," London Mayor Boris Johnson said in a statement along with Mastercard's index.

Well established international destination Bangkok was the other big winner in the index at third place with 12.2 million visitors who will spend $19.3 million.

"Bangkok's advantage is that it's a very tolerant culture," Hedrick-Wong told Reuters. "That explains its durability, especially attracting Europeans and Americans. I cannot imagine Western visitors doing the same thing in Malaysia, even China."

The Index, which encompasses 132 of the world's most important cities, is being marketed as a new map for understanding global connectivity.

Businesses and investors might find the Index's list of city growth rates of more interest than current rankings. Brazilian and Chinese cities also featured highly in the survey for both visitor numbers and spend.

"The growth patterns show how important cities are," says Hedrick-Wong, "and they're popping up from everywhere. They take on some really important local or regional significance overnight because of a new development."

Expect to hear much more about Recife and Belo Horizonte in Brazil, and Chengdu, Harbin, Xian and Guangzhou in China.

Using information gleaned from 87 airlines, national tourism boards, the United Nations and other global agencies, the MasterCard Index offers an optimistic overall forecast.

Total visitor numbers and cross-border spending will increase by 5.7 percent and 10.6 percent respectively for the top 20 destination cities in 2012.

The result is a bright spot in a period of slow world economic output, a persistent euro zone crisis and increased uncertainty in the financial sector.

"The growing need and desire to travel, especially by air, are set to expand in spite of the ups and downs of the business cycles," MasterCard's report said.

In a survey also out on Monday, by Mercer, London was ranked the 25th most expensive city in the world and the most expensive city for expatriates.

(Editing by Paul Casciato)

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