"The minister of the interior (Prince Nayef bin Abdul Aziz) is reported to have ordered the immediate detention and flogging of a 75-year-old woman, Khamisa Mohammed Sawadi, along with two Saudi Arabian men known only as Fahad and Hadyan," the London-based watchdog said.
"The Saudi Arabian authorities must not carry out the imminent flogging and imprisonment of an elderly woman and two younger men."
Amnesty said all avenues of appeal had been exhausted in Saudi courts against the trio's March conviction for being in the company of members of the opposite sex who were not close relatives.
"It is abhorrent that an elderly woman is at risk of 40 lashes," said the deputy director of the watchdog's Middle East and North Africa Program, Philip Luther.
"We urge the authorities to prevent the imprisonment and flogging of Khamisa, Fahad and Hadyan."
Maldivians paying homage to their Arab overloads.
The Arab overloads teach Maldivians to flog their women and there are currently 150 women (most are mothers) waiting to be flogged..