Updated

Human rights observers warn that Iran plans to execute a woman whose sentence to stoning has drawn international condemnation.

Contacts inside in Iran say authorities in Tehran have given the go-ahead to prison officials in Tabriz to execute Sakineh Mohammadi Ashtiani, possibly as early as Wednesday, though it's not clear yet by what method, Mina Ahadi of the International Committees Against Execution & Stoning told Fox News.

The 43-year-old mother of two had been sentenced to stoning for alleged adultery.

The Iranian government also claims Ashtiani had a hand in the murder of her husband.

Ahadi and her organization are calling on foreign governments to put pressure on Iran to issue a stay of execution, as they believe that Western governments are now Ashtiani's greatest hope, possibly her only hope.

They also are calling on the public to come out Tuesday and protest the latest development in the hope of raising attention and awareness to the case and press for release of Ashtiani, as well as her son and lawyer, who are missing.