Chilean officials say 33 miners trapped in a chamber 700 meters below the surface have not been told they will likely have to wait months before they are rescued.
Engineers are preparing to drill a 62 centimeter-wide rescue tunnel, but they say the work could take four months because of the depth and instability of the mine.
Rescue workers said Tuesday the miners are receiving nutritional supplements and medication through two narrow drill holes.
Officials spoke with the miners using a newly installed communications system late Monday. The men have said to officials that they are fine. The miners could be heard applauding and singing the country's national anthem.
Rescue workers said the men also asked for toothbrushes.
The 33 men became trapped more than two weeks ago after a shaft collapsed in the gold and copper mine near the northern city of Copiapo. They were found alive on Sunday. It is not clear what caused the collapse.
Joyous families have been writing letters to boost the morale of their loved ones. Officials say they are also working on plans to provide the miners with psychological help as they wait to be rescued.
The mine has a history of accidents and was reopened after having been closed in recent years.
Officials say the miners survived by reaching a chamber off the main mine shaft, and by eating small amounts of tuna and other food they found in the chamber.
Chile is the world's largest copper supplier.
Some information for this report was provided by AP, AFP and Reuters.