Including infamous al-Qaeda cleric Abu Qatada, who was jailed and then deported from the UK.

Via Guardian:

US counter-terrorism officials backed a high-stakes negotiation involving two of the world’s most prominent jihadi clerics as well as former Guantánamo detainees in an attempt to save the life of an American hostage held by Islamic State, the Guardian can reveal.

Emails seen by the Guardian show how tentative talks with the spiritual leadership of Isis to secure the release of Abdul-Rahman (Peter) Kassig began in mid-October and ran for several weeks, with the knowledge of the FBI.

Kassig – who converted to Islam while imprisoned for more than a year – was the most recent western hostage to be killed by Isis. The jihadi group announced his death on 16 November with a typically grisly video.

The ultimately unsuccessful initiative to save him was the brainchild of a controversial New York lawyer, Stanley Cohen, who has represented Osama bin Laden’s son-in-law and members of Hamas in US courts.

Cohen persuaded two senior clerics aligned with al-Qaida to intervene with Isis on behalf of the American. One, Abu Muhammed al-Maqdisi, is regarded as the world’s most influential living jihadi scholar, while the other, Abu Qatada, was once branded by a Spanish judge as al-Qaida’s “spiritual ambassador” in Europe.