International air passenger traffic rose 5.6 percent in September from a year ago, industry association IATA said Monday, describing the result as a "pleasant surprise."

However, the International Air Transport Association said it was bracing itself for poor months ahead amid falling business and consumer confidence and collapsing freight demand.

"September's strength in passenger demand was a pleasant surprise," said Tony Tyler, IATA director general.

The data "may reflect the robust conditions in emerging markets and travel booked earlier in the year when there was more economic optimism," added IATA.

European carriers were among the top performers for the month, with a 9.2 percent increase in international traffic during the month.

"The weak euro is enhancing Europe's attractiveness to tourists and creating export opportunities for business," said IATA.

Demand was also strong for Latin American carriers, growing 10.6 percent from the same period last year, while for Middle Eastern airlines, traffic was up 9.1 percent.

Asian airlines however recorded just 4.3 percent in growth, while North American carriers also posted a weak increase in demand of 1.2 percent.

However, freight demand was morose, with Asian Pacific carriers -- the biggest players -- reporting a 6.3 percent drop for the month.

European airlines also recorded a 2.4 percent contraction, while North American carriers reported flat freight traffic for September.