SYDNEY, Nov 10, 2008 (AFP) - Australia's biggest airline Qantas revealed Monday that passenger numbers were declining, as the global financial crisis is set to impact on the "Flying Kangaroo".

Overall passenger numbers decreased by 0.2 per cent in September 2008 over the previous year, according to the company's monthly traffic statistics.

The airline's revenue seat factor (RSF), which measures how many seats are filled across the airline's domestic and international flights, fell 2.1 percentage points to 79.8 per cent for the month, Qantas said.

It was the third straight fall in RSF since the financial year began in July.

In August, chief executive Geoff Dixon said airlines around the world were struggling against falling demand and rising fuel costs.

The airline has already slashed 1,500 jobs worldwide, cut growth and introduced other measures to combat the challenging market conditions.