Uncertainty over its future has forced Seafish to appoint yet another interim as opposed to permanent senior executive.

Dr Paul Williams, who has been research director of Seafish since joining in 2004, will take the reins as interim chief executive in October 2010, after current chief executive John Rutherford retires.

His appointment follows that of John Whitehead, who became interim chairman in June. The selection process for a permanent chief executive began last December but stalled when the body lost a challenge in the Court of Appeal over levies on fish imports. Seafish and Defra are ­co-defendants in the case, brought by British Seafood.

Seafish is now set for a Supreme Court showdown in its battle to retain the levy in March 2011. Failure could cost it up to 80% of its current income and result in numerous job losses.

It has already lost eight staff since the start of the case in March, when its head count stood at 96. They left voluntarily after finding other positions but have not been replaced.

In June Defra threw it a financial lifeline with a £200,000 loan to Seafish to keep it afloat. "John has made a huge contribution to Seafish in the almost nine years he has headed the organisation," Whitehead said of Rutherford's retirement. "Paul's appointment is a compliment to the calibre of the team he has built."

Rutherford will continue to assist the body in its ­ongoing legal battle.

Whitehead stepped in to replace Charles Howeson, who spent three years at the seafood authority.