An Iranian woman who was sentenced to death by stoning after being found guilty of adultery and helping kill her husband, will be executed Wednesday, according to a statement by a group that opposes stoning in Iran.

"The Islamic regime of Iran plans to execute Sakineh Mohammadi Ashtiani immediately," the International Committee Against Stoning (ICAS) said.

The group did not give details on the method that will be used to execute Ashtiani, but following an international campaign, Iran said a stoning sentence had been suspended.

Ashtiani was convicted of adultery in 2006 and, according to human rights activists, forced to confess after being subjected to 99 lashes. She later denied any wrongdoing.

ICAS has also alleged that Ashtiani's son and lawyer have been arrested and tortured by Iranian authorities.