Public relations executive James Morrissey has engaged the services of heavy-hitting Belfast-based brief Paul Tweed as he seeks to defend a defamation claim from Sir Anthony O'Reilly.

Morrissey, an adviser to Denis O'Brien, is being pursued over his role in circulating a report on corporate governance at Independent News & Media (IN&M) to the media.

The review was commissioned by O'Brien, and Morrissey is accused of leaking the document, which criticised IN&M, in advance of the media group's annual general meeting in June.

O'Brien owns more than 9 per cent of IN&M and has turned up the heat on Sir Anthony by alleging cronyism at the company. Tweed is a partner with Johnsons Solicitors and has a formidable reputation.

In May, his client Barney Eastwood reportedly got £300,000 (€443,600) in an out-of-court settlement with IN&M for an article that appeared in 2005 in the Irish Independent relating to his time as manager of boxer Barry McGuigan.

Other clients have included Jennifer Lopez, Britney Spears, Liam Neeson and Van Morrison. Sir Anthony is seeking a written apology from Morrissey, to be circulated to those who were sent the review. It is understood that Tweed has advised Simon McAleese Solicitors, which is representing Sir Anthony, that it is happy for their client to issue proceedings.

The report was written by Dr Stephen Davis of the Yale School of Management and Davis Global Advisors (DGA).

Sir Anthony's legal team recently wrote to Davis seeking an explanation for what it considers to be inaccurate and libellous statements in the review.

DGA is believed to have answered the queries in full. No action is being taken against O'Brien and it remains to be seen if Sir Anthony will take this all the way to court.

O'Brien and his advisers would surely like nothing more than to explore the extent of payments made by IN&M to Sir Anthony and other board members in the full glare of the press.