Egypt’s affiliate of the so-called ’Islamic State of Iraq and the Levant’ (ISIL) takfiri group threatened on Wednesday to execute a Croatian kidnapped in Cairo last month within 48 hours.

Egypt's affiliate of the so-called 'Islamic State of Iraq and the Levant' (ISIL) takfiri group threatened on Wednesday to execute a Croatian kidnapped in Cairo last month within 48 hours if "Muslim women jailed in Egypt are not freed."

The man is the first foreigner to be abducted and threatened with death by militants in Egypt since the unrest erupted two years ago.

In a video posted online by the group, the Croatian identifies himself as Tomislav Salopek working for French geoscience company CGG, and appears kneeling at the feet of a hooded man holding a knife.

Reading from a sheet of paper, he says he will be executed within 48 hours if Egypt's government fails to release Muslim women held in prisons.

Salopek, wearing an orange jumpsuit, said he was abducted on July 22 by the Sinai Province group, ISIL's Egyptian affiliate based in the Sinai Peninsula.

Formerly known as Ansar Beit al-Maqdis, the group changed its name when it pledged allegiance to ISIL in November.

In Zagreb, the foreign ministry said the "Croatian government... is doing its best to solve as soon as possible the difficult situation in which the Croatian citizen T.S. is," identifying the hostage only with his initials.

"Considering the very difficult and sensitive circumstances and in order not to make a difficult situation worse, we are not able to provide more detailed information at this moment."

Croatia's Foreign Minister Vesna Pusic will travel to the Egyptian capital on Thursday, the ministry later added in another statement.