National Party leader Bill English says the Government's proposal to ban foreigners from entering the New Zealand housing market may be scuttled by free-trade negotiations with China.

Public submissions close on Tuesday for the proposal, but Mr English said he'll be interested to see how our joint biggest trading partner will react to the ban - particularly as we try to improve trade relations with the Asian nation.

Asked whether he deemed the ban necessary, Mr English told The AM Show on Tuesday morning it's yet to be seen just how far the Labour-led Government actually get with it.

"The big challenge for the Government is that they're negotiating an upgrade with the Chinese of their free-trade agreement," he explained.

"They've yet to see whether the Chinese are going to take a deal where they give us something for our dairy and agricultural produce - which is really important to us - but whether they'll take worse treatment than Australia on this housing issue.

"I suspect that's the big test for this ban."

Mr English says despite being placed under pressure to impose a foreign buyers' ban while National was in Government, he didn't feel that was necessary - and he still doesn't now.

"We think the existing controls are sufficient. We don't think [Chinese buyers] have been a big influence in the market," he said.

"You just need to build more houses - and that's underway."

Prime Minister Jacinda Ardern announced in October that she would attempt to make an amendment to the Overseas Investment Act that would effectively ban foreign speculators from buying houses in New Zealand.

"We are determined to make it easier for Kiwis to buy their first home so we are stopping foreign speculators buying houses and driving up prices," she said at the time.

"Kiwis should not be outbid like this."

Non-residents or non-citizens will not be able to purchase existing residential housing, though Australian and Singapore citizens would be exempt.

Those who are not residents or citizens would still be able to purchase land and build new housing on it.

Newshub.