Discovery of the body on Thursday raised the death toll to 45.

The massive blast on Friday at the five-star Hotel Saratoga, a block from the iconic capitol building in a renovated area of Havana popular with tourists, left more than 100 people trapped, killed or injured. Fifteen remain hospitalised.

Officials say a gas leak caused the explosion.

Luis Carlos Guzman, chief of Cuba's firefighting corps, told reporters at the site of the blast that the woman whose body had been recovered, believed to be a waitress at the hotel, was "as of now, the last missing person".

The hotel was closed at the time of the explosion, but was set to open Monday. Most of those killed or injured were Cuban staff or passers-by, including a Spanish tourist and a pregnant woman. Several children from a nearby school were injured in the blast, and four were killed.

President Miguel Diaz-Canel has declared a period of national mourning in honour of those who died.

For days, Cuban rescue workers have sifted through massive piles of debris at the base of the hotel's neoclassical-style building, which is more than a century old. They have sought access to difficult-to-reach areas in the lower stories, where the last bodies were found.

The blast also seriously damaged two adjoining upscale apartment buildings and inflicted lighter damage to 17 structures within a two-block radius.

Australian Associated Press