Kateb al-Shammari said in a statement that Rumsfeld's departure after the Republicans' drubbing in mid-term congressional elections was a "positive step" for the detainees, since he was "primarily responsible" for the abuses there.
Rumsfeld was also a main advocate of keeping Guantanamo "outside international and US law", and he sanctioned the use of torture under the euphemism of "interrogation techniques", Shammari charged.
"In my capacity as a lawyer in this affair and agent for most of the families of Saudi detainees in Guantanamo, I reserve the right to file a lawsuit against Rumsfeld and the other (officials) responsible for the abuses committed against the detainees, and for their continued detention without legal justification," the lawyer added.
At least 90 Saudis are still being held at the notorious facility in Cuba, after 37 Saudi prisoners were repatriated. The bodies of two Saudi inmates, whom the US said committed suicide there in June, were also repatriated.
A lawyers' group representing Guantanamo prisoners said in Washington that Rumsfeld's resignation on Wednesday leaves him open to legal action over his alleged role in "authorising torture" of people held in the US "war on terror".

Copyright AFP (Agence France-Presse), 2006