New Zealand's leading businessman, Dr Roderick Deane, has stepped into the breach at Fletcher Challenge after the sudden resignation of group chairman Kerry Hoggard.

Accompanying a company statement Friday, Dr Deane said Mr Hoggard had no alternative but to offer his resignation, and the board had no alternative but to accept it.

"This was distressing for us all ... however, it does need to be emphasised that New Zealand law, and the rules of the company which derive from that law, are absolutely specific on these matters."

He said the situation Mr Hoggard found himself in regarding the company shares was "black and white".

"Had any staff members found themselves in a similar situation, they would have been asked to leave the company."

Fletcher Challenge described its new chairman - who has been a director of the company for five years - as "one of New Zealand's most able and respected businesspeople".

It said Dr Deane had decided to accept the position because of "his personal commitment to the successful restructuring of the Fletcher Challenge group of companies".

Dr Deane is also chairman of Telecom Corporation, ANZ Banking Group (New Zealand) and TransAlta.

He recently accepted a part-time position as Professor of Economics and Management at Wellington's Victoria University.

Fletcher shares came under pressure after the Hoggard bombshell on Thursday, but Friday's announcement, which came after the market closed, was greeted favourably by brokers.

Neil Paviour-Smith of Forsyth Barr said Dr Deane's appointment to the chair should give the market confidence that the restructuring of the Fletcher group will proceed.

"Dr Deane has been a key person in the restructuring process."

Arthur Lim of Ord Minnett said Dr Deane's appointment had turned a bad situation into a good one.

"There is no businessman in New Zealand who is held in higher regard by the international market than Rod Deane."

Former long-time Fletcher chairman Bill Wilson concurred, saying Dr Deane would be an excellent chairman.

"He has got one of the finest business brains in New Zealand."

Dr Deane was unavailable for further comment on Friday afternoon.

At the midday close of trading on Friday, before Dr Deane's announcement, Fletcher Building shares were up 6c to 274c, Energy up 3c to 483c, Forests up 2c to 78c and Paper down 3c to 131c.