Divers and rescuers are expected to enter a coal mine in northern state of Coahuila, where 10 miners remain trapped for the last six days, officials say.
Falling water levels have raised hopes that rescuers will be able to enter a flooded Mexican mine to look for 10 trapped workers.
By Wednesday or Thursday, the water level is expected to drop to around five feet, so "divers and rescuers will be able to enter," President Andres Manuel Lopez Obrador told media on Tuesday.
Authorities using an underwater drone equipped with a camera on Monday decided it was still too dangerous to enter the mine in Agujita in the northern state of Coahuila.
Images gathered by the drone showed obstructions and water turbulence, making it too risky to go inside, civil defence national coordinator Laura Velazquez said.
The focus so far has been on pumping out water from the 200 foot deep mine.
The water level in the shafts has fallen significantly, from more than 98 feet initially, but was still at least 32 feet deep, officials said.
Past mining incidents
Several hundred rescuers, including soldiers and military scuba divers, are taking part in efforts to save the miners, whose relatives were increasingly anxious nearly a week after the accident.
According to authorities, the miners were carrying out excavation work when they hit an adjoining area full of water.
Five workers managed to escape from the crudely constructed mine in the initial aftermath of the accident on August 3, but there has been no contact with the others.
Coahuila, Mexico's main coal-producing region, has seen a series of fatal mining accidents over the years.
The worst accident was an explosion that claimed 65 lives at the Pasta de Conchos mine in 2006.
Last year, seven miners died when they were trapped in the region.