Archie Norman's clearout of ITV's board has gathered pace as non-executive directors Heather Killen and Agnes Touraine agreed to step down ahead of the chairman's formal arrival next month.

Since the announcement of Norman's appointment in November, ITV has cut the eight-strong non-executive side of its board of directors in half. It is not known how many will be replaced: Norman has made clear that he would like to see ITV's 12-member board significantly cut.

"2009 has been by any standards a difficult and demanding year for the non-executive team at ITV and I thank Heather and Agnès for their support of me and Michael Grade through this period of succession," said Norman.

Killen, 51, and Touraine, 54, both joined the ITV board in 2007. Last week Sir George Russell, ITV deputy chairman, announced he was stepping down at the end of the year. Last month James Crosby, the former HBOS chief executive who ran the botched recruitment hunt for a chairman and chief executive, announced his intention to step down last month.

Earlier this week ITV named non-executive director Mike Clasper, the former head of airports operator BAA, as Crosby's replacement.

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