S4C says chairman Jones has quit, but he denies it
The S4C Authority has announced that its chairman, John Walter Jones, has resigned with immediate effect.
But he says he has not resigned and intends to continue with the Welsh language broadcaster until next spring.
The Department for Media, Culture and Sport, which is responsible for appointing the chairman, says it has not received a resignation letter.
His position now appears uncertain, as the authority's new vice-chair called the situation "bizarre".
The apparent resignation comes against the backdrop of months of turmoil for the Welsh language broadcaster, which is facing substantial budget cuts and has been told it must work much more closely with the BBC.
It does not have a permanent chief executive after Iona Jones left her job in controversial circumstances over the summer.
Despite the situation surrounding Mr Jones, the members of the authority are also under political pressure, with several Welsh Conservative MPs announcing they believed it was time for them too to step down.
In a statement, the authority said Mr Jones had confirmed to his fellow authority members on Tuesday night that he had tendered his resignation to Secretary of State for Culture, Media and Sport Jeremy Hunt.
It said: "This follows a meeting he held on 16 November with the secretary of state. Mr Jones later told the authority that his resignation would take immediate effect.
"We have not received formal confirmation of this decision from the DCMS and have had no contact with Mr Jones since last night's meeting."
In order to "ensure continuity and leadership for the channel", the authority said it had elected a vice-chair, Rheon Tomos.
The spokesman added: "There has always been unanimity within the authority of the importance of discussions with DCMS and the BBC regarding the future direction of S4C. Meetings have been held with both the DCMS and the BBC Trust and a further meeting will be held next week."
A DCMS spokesperson said: "John Walter Jones notified the secretary of state earlier this month of his intention to stand down at the end of March 2011."
Mr Jones told BBC Wales that he had an understanding with Mr Hunt that he would remain as chairman until March next year.
Alun Cairns, Conservative MP for the Vale of Glamorgan, said: "The actions of the authority members are bizarre.
"This demonstrates how unsuitable these people are to run a public body and to spend £100m of taxpayers' funds."
Earlier, Tory MPs said they believed members of the S4C Authority are "part of the problem".
'Cumbersome and expensive'
Aberconwy MP Guto Bebb told BBC Wales: "Some members of the S4C Authority are more concerned with scoring political points against the coalition government than trying to move S4C forward to a secure future.
"We've come to the conclusion as a group of MPs, especially after yesterday's evidence to the Welsh Affairs Select Committee, that the S4C Authority are part of the problem rather than part of the solution."
Giving evidence to Welsh MPs on Tuesday, the executive chairman of the independent television company Tinopolis, Ron Jones, said S4C had thought of itself as a "big and important organisation" and should think more like a "small organisation once again".
Former BBC Wales controller Geraint Talfan Davies told the inquiry that he believed the details of the deal to fund the channel from BBC funds "sounded cumbersome and expensive".
He told MPs that the arrangements being suggested by the DCMS, were "not a workable structure".
The S4C Authority took effective control of the channel after its chief executive quit.
It is currently advertising for candidates to replace Ms Jones.