Ninety-three people died in Van province and 45 in the Ercis district, Prime Minister Recep Tayyip Erdogan told reporters, during an immediate visit to the quake region to see for himself the devastation.
An earlier toll had given 70 dead including 50 in Ercis, a district of around 100,000 people in the same region as Van.
The situation in Ercis is more grave, said Erdogan, adding that around 55 apartment buildings collapsed, raising fears that the toll could increase as many people were trapped under rubble.
Television footage showed search and rescue teams recovering bodies from the collapsed buildings in Van and Ercis.
Most people are expected to spend the night outdoors, with the temperature expected to dip to three degrees Celsius.
Some 1,275 search and rescue teams from 38 Turkish cities as well as 145 ambulances were sent to the quake region, according to media reports.
The military said six battalions were also involved in search and rescue efforts, in a statement posted online.
The epicentre of the quake, which struck at 1041 GMT, was at Tabanli in Van province, Turkey's Kandilli institute said. Two aftershocks had hit the villages of Ilikaynak and Gedikbulak in particular, it added.
The quake was also felt across the border in northwestern Iran, causing some panic in major cities, Iranian media reported. They did not report any deaths or serious damage.
The US Geological Survey initially measured the quake at 7.3 magnitude but later downgraded it to 7.2. It registered many aftershocks, the latest of which was of 6.0 magnitude.
The quake that struck Van, a large eastern city populated mainly by Kurds, was Turkey's strongest in years.
In 1999, two strong quakes in the heavily populated and industrialised regions of northwest Turkey left some 20,000 dead. A powerful earthquake in the town of Caldiran in Van province killed 3,840 people in 1976.