Japan opened a communication channel with Islamic State in the decisive stages of the recent hostage crisis but was unwilling to use it to start negotiations, according to a Tokyo-based Islamic scholar who served briefly as an intermediary.

Hassan Ko Nakata, 54, whom police suspected was a recruiter for the Islamic State group, was asked by the Foreign Ministry to pass on a message to the group at the peak of the crisis last month, according to Nakata, associates and records reviewed by Reuters.

The request, which had not been previously revealed, shows the government appeared ready at one point to talk to Islamic State to free the two Japanese men who had been captured in Syria for ransom, despite officials' public vow not to give in to terrorism.