Mike Ruddock (L) stated he was resigning for family reasons

Ruddock stepped down as Wales coach on 14 February, saying he had "decided to put his family first".

But it has emerged that contractual differences played a greater part in his departure.

The WRU said it had reflected the views of Ruddock, who has always said he resigned for family reasons.

Meanwhile the Welsh Rugby Union's former group chief executive, David Moffett, has said there are further issues surrounding the saga which "some people might not like".

The BBC Wales investigation revealed Ruddock was unhappy with key points in his contract which he believed were missing or incomplete - including issues over grievance procedure and sick pay.

The investigation also revealed the WRU told rugby clubs in Wales at closed meetings during its "red zone roadshow" that there had been differences over contract details with Ruddock.

But Wales manager David Pickering and WRU chief executive Steve Lewis also said the terms on offer to Ruddock were almost identical to those made to the two previous coaches Steve Hansen and Graham Henry.

WRU calls special meeting of clubs

The BBC understands that money was not an issue with Ruddock's contract, despite the fact Henry and Hansen were paid through their companies - which has tax advantages - and Ruddock would have been employed staff.

Manager Pickering has previously said the offer Ruddock had "shook hands" on in August 2005 guaranteed him �400,000 over two years with a "possible upside" of �550,000.

The contract would have "made him earn twice as much money as any other employee in the union", he said.

The WRU said the reasons given by Lewis for Ruddock's resignation in February were only those given to the WRU by the coach.

Ruddock has never deviated publicly from his first statement that he had stepped down as coach for family reasons.

Meanwhile, in an interview on BBC Radio Wales on Friday, former WRU group chief executive David Moffett said there was potentially uncomfortable information which had not yet emerged.

He urged the WRU to be transparent at a special general meeting (SGM) of its 245 member clubs on 23 April.

'Red herring'

Asked by presenter Richard Evans what he was trying to say, Mr Moffett said: "I think you're going to have to read into what I said that I don't think that all the people involved in the Mike Ruddock saga would necessarily want all the issues to come out."

"I'm not sure that everybody involved in that particular issue would want all the facts to come out, and then it might transpire that the issue about Mike Ruddock is just a bit of a red herring and there are other issues at work here," he said.

"If that includes providing the clubs with some information that people would prefer that they didn't get, then so be it... if that's what it takes to put a line under this," he added.