Fatalities from the earthquake rose to 24,596 on Saturday. Of that number, 21,043 were located in Turkey, President Tayyip Erdogan said.
Speaking during a visit to the Turkish city of Adana, Martin Griffiths said what happened in the area around the epicentre of the quake was one of the worst natural disasters to hit the region in a century.
“I think it is difficult to estimate precisely as we need to get under the rubble but I’m sure it will double or more,” the UN emergency relief co-ordinator told Sky News.
“That’s terrifying. This is nature striking back in a really harsh way.”
Before adding: “It’s deeply shocking… the idea that these mountains of rubble still hold people, some of them still alive.
“We haven’t really begun to count the number of dead.”
The Disasters Emergency Committee (DEC) which brings together 15 leading UK aid charities says its appeal has raised £52.8 million in two days – including £5 million in aid match from the UK Government.
On Friday, a ten-day-old baby was freed after spending almost half its life trapped under rubble of the earthquakes that struck Turkey and Syria.
His eyes wide open, Yagiz Ulas was wrapped in a shiny thermal blanket and carried to a medical centre in Hatay province, on Friday. His mother was also carried on a stretcher, videos showed.
At least seven children were rescued in Turkey on Friday and three in the Syrian city of Jableh, state media reported.
Incredible footage released by the London Fire Brigade shows Edmonton-based firefighter Dom Mabbett among rescuers who reunited a mother with her young daughter in Hatay.
Andy Roe, Commissioner of the London Fire Brigade (LFB), said the 12 members of his crew currently deployed in the disaster zone were setting an example for their colleagues.