Lord Justice Leveson has said he has a "vast and difficult task" ahead and needs to make sure everyone involved in the inquiry into press ethics and behaviour was "pulling in the same direction".

He told a preliminary hearing at London's high court that he wanted to learn as much as possible about journalism and urged all the barristers and solicitors in the court room to tell him if he was missing any "perspective".

It was "critically important through this inquiry that I have the help of everyone", he said.

Leveson added: "I have a vast and difficult task to address within a comparatively short period of time. I will only start to be able to achieve a sensible resolution … if everyone is pulling in the same direction, albeit from different standpoints."

At the hearing, he made it plain that he and he alone would reach his conclusion and make recommendations about the future of the press when he reports back to David Cameron next year.

He also issued further details about the dates and potential subject areas of the seminars he will hold ahead of the full inquiry.

The first seminar on 6 October will be chaired by Sir David Bell, the former chairman of Financial Times, and will explore issues relating to privacy and the press.

A second seminar has been scheduled for 12 October but no details of the subject matter have been released.

Leveson said a list of witnesses had been drawn up to appear at the seminars but the letters had not been posted because of a challenge by Associated Newspapers on Wednesday on the role of the "assessors", or experts, appointed to advise the judge. Associated is concerned that there is not an assessor with tabloid journalism experience among the six appointed by Leveson.

After some legal debate he clarified his vision for the seminars – unlike the hearings when the inquiry proper gets under way, those invited will be asked to speak informally and will not be under oath.

In each seminar, three people will give a 10-minute presentation "and then it is open to anybody else [in the audience] to contribute and add to the debate".

Leveson did not say whether the audience would be invited or open to the public.

The seminars will be recorded, streamed live on the Leveson inquiry website and transcripts will be made available.

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