Labor Secretary Francisco Salazar said he was confident contact would be established with the trapped miners soon.
Authorities have not heard from the miners since the explosion early on Sunday trapped them 150 meters (500 feet) below ground at the Pasta de Conchos mine near San Juan de Sabinas, in the northern state of Coahuila.
"We have not had any communication with them since the cave-in," Coahuila Governor Humberto Moreira told Mexican television.
Mr Salazar said that a team 60 diggers had advanced to within 50 meters of the trapped miners, and were working to reinforce the collapsed area.
The miners are believed to be trapped between 700 and 1,200 meters along the two-kilometer-long tunnel.
Rescuers were forced at times to use their bare hands to try to open a narrow blocked passage in the mine. Rescue operations moved slowly, as heavy digging equipment was not used for fear of triggering a new explosion.
The miners were trapped following an explosion, apparently caused by gas at a mine owned by Industrial Minera Mexico.
There were 87 miners inside the shaft at the time of the blast. Ten workers escaped safely, while 12 others who were rescued suffered serious injuries, including burns.
About 200 distraught wives, children and parents of the missing workers maintained their vigil at the mine's entrance, nearly 60 hours after Sunday's 2:20 am blast, desperate for word about their loved ones' fate.
Norma Vitela's husband, Jose Guzman Angel, is among the 65 trapped miners.
"They always said the mine was bad, (my husband) said that it smelled heavily of gas," said Vitela, 53, as her daughter clung to her, weeping. "But they did nothing, they told the miners everything was fine."
The workers were all on the overnight shift at the mine, located just outside San Juan de Sabinas, a town of some 40,000 people.