COPENHAGEN, Denmark - The death toll from Monday's major earthquake in Turkey and Syria is liable to rise significantly above the provisional tally of more than 2,600, the World Health Organization forecast.

"There's continued potential of further collapses to happen so we do often see in the order of eight fold increases on the initial numbers," the WHO's senior emergency officer for Europe, Catherine Smallwood, told AFP.

"We always see the same thing with earthquakes, unfortunately, which is that the initial reports of the numbers of people who have died or who have been injured will increase quite significantly in the week that follows," Smallwood added.

Since the 7.8 magnitude quake struck at 04:17 am (0117 GMT) on Monday at a depth of about 18 kilometres (11 miles) near the Turkish city of Gaziantep, some 60 kilometres from the Syrian border, the toll has swiftly risen, nearing 2,700 by the evening as rescuers battled to locate survivors trapped under the rubble of thousands of collapsed buildings.

Biting mid-winter temperatures and blizzard conditions rendered the rescue extra difficult and put at risk survivors left without shelter.

"For other people who can't go back to their homes they will be meeting and gathering in collective environments. And that will also pose particular risks if they're not well catered for, if there's no heating, but also due to overcrowding," said Smallwood.

One such risk would be circulation of respiratory viruses, she explained.

Turkey is situated in one of the world's most active seismic zones, with Monday's tremor occurring along the East Anatolian fault -- across country from a North Anatolian fault line quake which killed more than 17,000 people in 1999.

Monday's temblor was felt as far away as Greenland, seismologist Tine Larsen, from the Geological Survey of Denmark and Greenland, told AFP.

She said that, within minutes, the shaking was felt on Greenland's east coast, as were several aftershocks.