Pinchao said the three Americans – Marc Gonsalves, Tom Howes and Keith Stansell – arrived 10 months ago at the camp where he, Betancourt, a former presidential candidate, and eight more hostages were being held by Farc.
The three contractors were on a drug surveillance mission in Colombia's cocaine-producing southern jungle when their plane crashed on February 13, 2003.
Pinchao said the mission of his captors was to keep their prisoners alive, but "if there was no more possibility of doing so, then they weren't allowed to let [government] troops to take us out either."
Pinchao said Gonsalves was suffering from hepatitis at the time of his escape and many of the prisoners were struggling to stave off malnutrition as a result of a pure diet of rice and beans.
Pinchao was found on Wednesday by an anti-narcotic police patrol after trekking and swimming for 17 days in the jungle.
Uribe, hearing Pinchao describe how he was treated by Farc members, said that "Farc's concentration camps are crueler than those of the Nazis" and renewed calls to his military to free the hostages.
"[Farc] have already told us that they will kill them. If there is a rescue attempt, they will kill them."
Juan Carlos Lecompte, Ingrid Betancourt's husband
"Generals we're going to rescue Ingrid Betancourt," said a visibly angered Uribe at a military ceremony on Friday.
"And let there be no doubt in the US Congress that we're also going to militarily rescue the Farc's three American hostages."
France immediately criticised the decision by Uribe to send in the army to free the French-Colombian, Betancourt, and three Americans.
"We are verifying what Mr. Uribe has said exactly," a spokesman for French Foreign Minister Bernard Kouchner said on France Info radio.
Nicolas Sarkozy, the French president, met with Betancourt's two teenage children, their French father, and Betancourt's sister, Astrid, on Friday.
Betancourt's daughter Melanie, told France 2 television, that Uribe "is mocking" Sarkozy and France by ordering the military operation.
However, on Saturday, Uribe said he was open to any suggestions France's new president may have to free a Franco-Colombian senator kidnapped five years ago.
"We are respectful and receptive to any ideas he may have," Uribe said.
In Bogota, Betancourt's husband, Juan Carlos Lecompte, said that Uribe's order put the lives of all of the hostages at risk.
Farc "have already told us that they will kill them. If there is a rescue attempt, they will kill them," Lecompte said on Friday
Pinchao, who had a son born while in captivity, methodically plotted his escape for months, quietly storing away rice for month in preparation for an eventual escape attempt.