Protester wearing a Guy Fawkes mask, symbol of the group Anonymous, takes part in a Brussels protest [Reuters]

Hacker group Anonymous has released a recording of what appears to be a conference call between the US Federal Bureau of Investigation and Scotland Yard held last month to discuss operations against the group.

The audio of the nearly 17-minute conference call was posted on YouTube along with an email invitation from an FBI  agent setting up the call for January 17.

The FBI did not immediately return phone calls or emails asking about the Anonymous claim. A spokesman for Scotland Yard told the AFP news agency: "We are looking into the reports."

The email invites members of European law enforcement agencies to take part in a conference call "to discuss the on-going investigations related to Anonymous, Lulzsec, Antisec, and other associated splinter groups".

The email, with details for accessing the call, was sent to law enforcement officials in Britain, France, the Netherlands and others. The only people who identify themselves on the call are from the FBI and Scotland Yard.

In a message on Twitter, Anonymous posted links to the audio recording and said the FBI "might be curious how we're able to continuously read their internal comms for some time now".

At various times during the call, the British and US participants mention Jake Davis and Ryan Cleary, two British teenagers who were arrested last year over hacking.

Davis is charged with hacking into websites, including that of Britain's Serious Organised Crime Agency, which was out of service for several hours on June 20 after apparently being targeted.

Cleary was detained in connection with a month-long global rampage last year by the Anonymous splinter group Lulz Security.