Peter Madden, who is in Lima, said Melissa Reid, 20, from Lenzie, near Glasgow, and Michaella McCollum, 21, from Northern Ireland, were expected to lie “almost on the floor”.
The two women have been refused bail and could spend up to three years in prison awaiting trial.
Following a public court appearance last night, McCollum and Reidwere formally charged with the promotion of drug trafficking and denied bail.
During the hearing, the judge reportedly asked the pair why they did not ask for help when they arrived at Lima airport, to which they replied they were threatened by “someone anonymous”.
They face a maximum prison sentence of 15 years if convicted, the prosecutor’s office in Callao, near Lima has said. The pair must now prepare for their first full interrogation, expected to be in about a fortnight.
Medical and psychological tests will be carried out before officials can decide where they should be held. It is likely they will be sent to the Ancon 2 prison, outside Lima, where more than 300 foreign women are held, most of them Europeans on drugs charges.
Mr Madden, Ms McCollum’s solicitor, criticised the conditions in which the women have been held.
“The conditions inside the holding cells are pretty grim,” he said. “They are expected to lie almost on the floor. There is a sort of sponge bed, which is not acceptable, it is not clean.
“They have not been offered any food,” he added. “To me, that is unacceptable.”
Officials in Peru believe they have enough evidence to bring a successful conviction against the pair.
A spokesman for the state prosecution service said yesterday: “The Callao state prosecutor’s office has filed a criminal suit before the courts against Michaella McCollum and Melissa Reid as suspected authors of a crime of drugs trafficking.
“Peru’s penal code punishes this crime with a custodial sentence of eight to 15 years. State prosecutors have gathered enough evidence pointing to the alleged responsibility of both women, which means that in the course of the investigations against them conducted so far, the allegations against them have not changed.”
They were set to be transferred to a local jail yesterday, while officials decide where to send them next. A prison service spokesman said: “They have yet to be handed over to us, but we expect that to take place this week.”
Reid and McCollum were arrested on 6 August as they tried to board a flight to Spain from Lima. Anti-drugs officers found more than five kilos of cocaine disguised as food products in each of their suitcases. They spent two weeks in police cells before being handed over to state prosecutors.
The pair, who had been living and working in bars in Ibiza over the summer, claim they were forced to Peru to bring back drugs to Europe by armed Colombian gangsters, who threatened them and their families if they failed to obey orders.Reid’s father William, who has flown out to Peru, insists his daughter is innocent.
He said: “I can only go by what I have been firmly told by the girls. The two girls’ stories are very tight, very consistent, with a lot of detail, and they seem to be telling the truth, as far as I can gauge.”