The majority of Kiwis back the new gun laws the Government put in place last week, according to a new poll.

But almost one in five people surveyed in a 1 News/Colmar Brunton poll say the ban does not go far enough.

The legislation, passed under urgency last week, means most semi-automatic firearms and some pump action shotguns, as well as certain large-capacity magazines, have been made illegal.

The law had the support of most MPs in the House, with the exception of Act's David Seymour who opposed the urgency process.

The poll – taken after the terror attacks on two Christchurch Mosques on March 15, which claimed the lives of 50 people – showed that 61 per cent of Kiwis thought the new law was "about right".

A further 19 per cent of people said the law does not go far enough and 14 per cent of those surveyed thought the legislation went too far.

Just 5 per cent of people said they did not know.

Breaking the numbers down further, 70 per cent of those who thought the new law was about right were Labour supporters.

When it comes to those who think the Government went too far, 21 per cent were National Party supporters.

Those aged 70 and older were among those most likely to think the Government had not gone far enough with the rules.

Prime Minister Jacinda Ardern had previously stated that she thought most Kiwis would back the Government's moves to ban semi-automatic weapons.

Speaking in the House at the third reading of the bill last week, Ardern said she could not fathom how weapons that could cause such destruction and large-scale death could have been obtained legally in this country.

"I could not hand-on-heart go down and face not just the media, not just the public, but the victims that had been left behind from this terror attack and tell them hand-on-heart that our system and our laws allow these guns to be available and that was okay. Because it was not."