New Zealand prime minister Christopher Luxon has survived a second leadership challenge in four months, securing the backing of his ruling National Party ahead of the November general election.

After a more than three-hour meeting with his MPs, Mr Luxon said the party was “united” and “determined to win this election”.

“There was a confidence vote in my leadership this morning at our caucus meeting, and I have the full support of our caucus,” Mr Luxon said.

Mr Luxon arrived with his entire senior caucus, including his deputy Nicola Willis and National Party president Sylvia Wood by his side. Erica Stanford and Chris Bishop, the MPs rumoured to be plotting against him, were also there.

Mr Luxon addressed the media for just 76 seconds and didn’t take any questions from reporters.

He said: “As you know, this is an absolutely pivotal election with some very, very serious issues at stake in New Zealand.

“We think we have made tremendous progress as a government, rebuilding economic growth, financial discipline, restoring law and order, and certainly strengthening education and healthcare, but we also acknowledge that we have a lot more to do.”

He added: “Our plan to fix the basics and to build the future is a positive plan, a very positive plan, to help New Zealand realise the innate potential that it has.”

“It’s also an opportunity to frame the choice for voters, which is crystal clear on 7 November, an opposition that wants to take New Zealand backwards, or a national government that wants to fix the basics and build the future with a plan that takes New Zealand forward,” he said.

Rumours of a leadership coup against Mr Luxon began circulating on Monday and reached fever pitch within 24 hours, forcing the prime minister to summon his MPs to Wellington for an urgent meeting where a confidence vote was expected.

Mr Luxon, who survived a similar challenge in April, is facing mounting pressure as National’s poll support remains weak amid sluggish economic growth and a string of political missteps.

Last week, he faced criticism after suggesting, on live radio, a referendum on the electoral system without consulting colleagues, while an earlier speech telling small businesses to “be adult” sparked a backlash and forced him to apologise.

Mr Luxon’s National Party won the 2023 election on promises to cut living costs and taxes, but its support has since weakened as unemployment reached an 11-year high of 5.6 per cent.

A new 1News Verian poll put Mr Luxon’s preferred-prime-minister rating at a record-low 17 per cent, although he remains ahead of his rivals.

Stuff NZ reported that Chris Penk, a senior National Party MP, had been sacked from his ministerial positions by Mr Luxon after allegedly being involved in efforts to challenge his leadership.

Mr Penk has denied wrongdoing but has now announced that he “will not seek re-election as an MP in November”, effectively ending his nine-year career in parliament.

Political commentator and author Dr Claire Robinson told The Guardian that the urgent confidence vote suggested that there was something wrong inside the party. “But they’ve clearly made a risk assessment: is it better to stick with what people know rather than pick an untested leader?”