WELLINGTON (Reuters) - A New Zealand Labour government will still want to be part of the stalled Trans-Pacific Partnership (TPP) trade deal but only if it allows for foreigners to be banned from buying existing homes, opposition leader Jacinda Ardern said on Tuesday.

New Zealand's new opposition Labour party leader, Jacinda Ardern, speaks during an event held ahead of the national election at the Te Papa Museum in Wellington, New Zealand August 23, 2017. REUTERS/Ross Setford

Labour, firming as the frontrunner ahead of the National government in a Sept. 23 election, wants to curb overseas buyers’ home purchases in a bid to cool the housing market and make home ownership more affordable for New Zealanders.

Foreigners with the right to live in New Zealand would be exempt from Labour’s proposed ban, which would still be at odds with provisions in the TPP trade deal as well as New Zealand’s free trade agreement with South Korea.

“It is an agreement we want to be part of, but we also want to maintain our ability to legislate under our laws to protect what is an overheated housing market,” Ardern said.

“We want to be in there but our housing bottom line is pretty firm for us,” she told New Zealand media.

The original 12-member TPP, which aims to cut trade barriers in some of Asia’s fastest-growing economies, was thrown into limbo in January when U.S. President Trump withdrew from the agreement.

The remaining 11 members have said they remain committed to the deal, but implementation of the agreement linking 11 countries with a combined GDP of $12.4 trillion has stalled.

Ardern, who has almost single-handedly changed Labour’s election chances since becoming leader in August, has made home ownership a campaign focus.

She has criticized National for failing to tackle a housing crisis during nine years in government, promising to build more affordable homes and to crack down on foreign speculators.

Labour wants to reconsider New Zealand’s role in the TPP if foreign investment provisions are not restricted.

Banning foreign investment in existing homes would also mean having to renegotiate New Zealand’s trading agreement with South Korea, although its free trade deal with China already provides for restrictions on foreign investment.

“Korea has the same carve-out ... for themselves so they can restrict New Zealanders ... Australia has that same carve-out in their agreement with Korea, so we don’t anticipate that would be a significant sticking point,” she said.

National criticized Labour’s plans to renegotiate the trade agreement with South Korea, describing it as an “ill-thought out and vague” policy.

Support for Labour rose to 41.8 percent in the latest average of opinion polls, nudging above National’s 41.1 percent.