About 90 million passengers used the Kuala Lumpur International Airport (KLIA) last year, a 100 per cent increase from 45 million in 2007, Deputy Transport Minister Datuk Ab Aziz Kaprawi said.

He attributed the increase to Malaysia's success in making Kuala Lumpur the premier transit centre in the region and expected the figure to grow in future following efforts to allow 'pre-clearance' at KLIA for flights to Saudi Arabia.

"This will be the only pre-clearance (hub) for Saudi Arabia in the world," he told reporters after opening the Johor Bahru UMNO Delegates' Conference here, Friday.

Ab Aziz said the government also had plans to expand the airport after 2020.

In another development, Ab Aziz said the Digital Free Trade Zone (DFTZ) to make KLIA an online trading centre, would begin operations this November.

"Currently, it (DFTZ) is being built over 90 acres of land, and is expected to help small and medium enterprises (SMEs) to market their products globally," he said.

DFTZ was launched by Prime Minister Datuk Seri Najib Razak in March, during Chinese Internet mogul Alibaba Group executive chairman Jack Ma's visit to the country.

It will combine physical and virtual zones with digital services and supplementary online services to facilitate international-based Internet and e-commerce innovation.

Headquartered at KLIA Aeropolis, DFTZ will be the hub of air cargo and logistics, involving the Alibaba Group, Lazada and POS Malaysia.