He joined the board in 2002 and has been senior independent director since June 2006.

He acted as interim chairman from February 2008 until Greg Lock's appointment in July that year.

Lock said: "We are immensely grateful to Cliff for his dedication over the last eight years and wish him well in his future endeavours.

"The nominations committee has appointed an executive search firm to assist in recruiting a suitable candidate to replace Cliff on the board and its sub-committees, including the chair of the remuneration committee."

Story provided by Business Financial Newswire