Prime Minister Helen Clark has described as "patronising" a comment by National leader Don Brash that he is not as tough on her because she is a woman.

The pair went head-to-head in the first live television leaders' debate on TV One last night.

Miss Clark, confident and aggressive on the hour-long programme, often forced Dr Brash into defensive explanations of National's policies.

After the debate, Dr Brash told reporters he restrained his attacks because Miss Clark was a woman.

"Well, I think it's not entirely appropriate for a man to aggressively attack a woman and I restrained myself for that reason," he said.

"Had the other combatant been a man my style might have been rather different.

"I try to be courteous to everybody and prefer a reasoned and rational debate rather than shouting over my opponent," Dr Brash said.

A National Party spokesman today told NZPA that Dr Brash said he thought it set a "poor example for men to be seen shouting at women".

Miss Clark's response was: "It's patronising."

Dr Brash has been criticised for his treatment of women in his caucus -- he stripped National MP Katherine Rich of her welfare portfolio for failing to publicly support aspects of his Orewa II speech on welfare and took the Moari affairs portfolio off Georgina te Heuheu when she criticised as Maori bashing his Orewa I speech.

Green Party co-leader Jeanette Fitzsimons has said women would be back "in the kitchen" if Dr Brash had his way.