BAA, owned by Spanish infrastructure group Ferrovial (FER.MC), on Tuesday said 9.6 million passengers passed through its five UK airports last month, compared to about 10 million in July 2011.

London Heathrow - Europe's busiest airport - handled 6.6 million passengers, down 4.4 percent year-on-year.

"The drop was more pronounced in the second half of the month and it is likely that the Olympics played a part, with UK passengers staying at home as well as non-Olympic visitors from overseas choosing to defer their journeys," said BAA's chief executive Colin Matthews.

BAA, which has been criticised in the past for its handling of snow and volcanic ash related disruptions, said years of planning helped it cope well with the influx of passengers flying into London for the Games.

"Seven years of hard work and planning, the warmth and enthusiasm of more than a thousand volunteers and additional Border Force staff produced our strongest ever passenger satisfaction scores," added Matthews.

At Heathrow domestic traffic rose 1.2 percent on last year, while European traffic, which was significantly affected by the Olympics, fell 6.6 percent.

July passenger traffic at London Stansted airport fell 5.3 percent year-on-year, Southampton dropped 9.5 percent and Glasgow was down 0.5 percent. Aberdeen, though, saw an increase of 4.4 percent.

The amount of cargo carried across the group's five airports was up 0.6 percent on the same month last year, BAA said. (Reporting by Rhys Jones; Editing by Neil Maidment)

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