The Government seems likely to soften proposed defamation laws to ensure they are passed.

Associate Justice Minister Margaret Wilson slipped a defamation clause into the Electoral Amendment Bill (No. 2) at the last minute.

The clause would make publishing untrue statements that defame a candidate and are aimed at influencing a vote a criminal offence punishable by up to three months in jail or a $5000 fine. Defamation has not been a criminal offence for almost 10 years, and before then prosecutions were rare.

The Prime Minister said yesterday that Ms Wilson would talk to the Green Party about amending the clause to ensure its support and, therefore, the bill's passage.

"We're discussing the form of amendment," said Helen Clark. It was likely to include the words "knowingly or recklessly - something like that".

Helen Clark said the Government had had "positive" consultations with the Greens on the bill three times before it went to Parliament.

"Their attitude was checked again just before the matter was debated and put to a vote in Parliament.

"[But] I think, in light of the fact that they've now expressed reservations, it's best to go back and talk to them about it."

Greens co-leader Rod Donald admitted his party had been happy with the clause, but its effects had since been pointed out "in no uncertain terms".

"We were looking at it principally as a measure to curb candidates from telling outrageous lies," he said.

"We hadn't considered the impact on the media and I think it would be fair to say that the Government hadn't actually highlighted that impact."

Helen Clark said she had no objection to the principle of the clause, as people put themselves in a unique position when they ran for election.

"But if we can improve the wording to make it sure that it really is a reckless act, a calculated act, then that's fine," she said.

The chairman of the Commonwealth Press Union freedom committee and editor-in-chief of the Herald, Gavin Ellis, welcomed the likely change. But he urged the Government to do more than simply insert a word.

"I would still be unhappy if the clause still referred to defamation, because it will still have the effect of putting back into law an aspect of criminal libel that this country got rid of a decade ago," he said.

"They need to ensure that the clause does not either deliberately or inadvertently reintroduce into New Zealand law the concept of criminal libel."