At least 45 flights between Europe and Asia were canceled Saturday, with the number expected to rise to surpass the previous day's 60 cancellations.

Officials don't known when the skies in Europe, one of aviation's most congested areas, will be safe again. Volcanic ash limits visibility and is capable of knocking out jet engines.

It could be more than a week before the chaos is sorted out, warned David Epstein, corporate affairs manager for Qantas, Australia's largest airline.

Qantas said its five flights that normally would go from Australia to Europe via Asian cities were flying Saturday - but only as far as the Asian stops.

"It's best to put safety before schedule, and where there's any question of volcanic ash being in the air we would prefer to take the safe approach rather than risk it to get flights in," Epstein told reporters in Melbourne.

At Beijing's international airport, most of the flights to Europe leaving Saturday had been called off, including ones to London, Paris, Rome, Frankfort and Copenhagen.

In Hong Kong, at least one airline, Cathay Pacific, was already canceling some Europe-bound flights for Sunday.

A dozen passengers from South Korea's Incheon International Airport were grounded Saturday, said airport staffer Jeon Ji-ye.

Southern Iceland's Eyjafjallajokull (ay-yah-FYAH'-plah-yer-kuh-duhl) volcano eruption sent ash several miles (kilometers) into the air, with winds pushing the plume south and east across Britain, Ireland, Scandinavia and into the heart of Europe. Two-thirds of flights in Europe were canceled, sending hundreds of thousands of stranded passengers in search of hotel rooms, train tickets or rental cars Friday.

About 2,000 Qantas customers are stuck in Singapore, Bangkok and Hong Kong. If they don't want to wait, they are being offered flights to non-European destinations or back to Australia, Epstein said. About 100 international customers are being put up in hotels in Australia.