ICRC spokesman in Amman Kassis Mueyin would not specify if the detainees, who were among eight Arabs released from Iraq, were being held by US or British troops.
But he admitted that the men were found "in a British military hospital in southern Iraq with severe injuries". He would not discuss the nature of their injuries.
Spokesman for British troops in Basra Hisham Halawi said all three lost limbs, adding they were Lebanese, Syrian and Jordanian.
They were initially being held by American soldiers, he added.
Five Jordanians, two Syrians and a Lebanese arrived in Amman on Saturday from Iraq.
The international organisation has had access to detainees and prisoners of war in Iraq since late March. During its missions, it sends messages from detainees to their families on their well-being.
The three injured prisoners had been among detainees who had been communicating with their families through the ICRC, said the Amman spokesman. During one of the missions, an ICRC team discovered the three had sustained the injuries, said Mueyin.
There have been past accusations
of prisoner maltreatment in Iraq
When asked if the organisation was concerned with the treatment of detainees in Iraq, he said:" When we are faced with such conditions the ICRC intervenes with the occupation authorities."
According to international laws, the safety and well-being of prisoners is the responsibility of the occupying forces, said Mueyin.
The ICRC is willing to help the disabled former detainees with their treatment after they are repatriated, he added.
Halawi said the three men had sustained injuries during an "accident" in September.
The British spokesman said the prisoners stepped on a landmine during an "area cleaning" activity.
They were transferred to a British military hospital at Shabaa camp where they received artificial limbs from the Red Cross and began their recovery, he told Aljazeera.net.
Halawi said he was "surprised" that there were suspicions that the detainees had been maltreated.
He did not know if they were being held for participating in anti-occupation attacks.
Jordanian Abd Allah Zaidan's brother, Abd al-Rahman, was among those detainees released on Saturday.
Abd Allah told Aljazeera.net that his brother was studying English translation at an Iraqi university when he was captured in April for allegedly participating in the resistance against occupation forces.
Abd Allah, who has yet to see his brother, dismissed the accusation, saying the occupation forces in Iraq are not "differentiating between students, fighters and killers".
"Because he was an Arab, he was detained," said Abd Allah, referring to his brother. "But he was just a student."