"I'd be surprised if there was any caucus where there wasn't talk about who's next, or who's third or fourth in line. But the conflation of that into some threat on my leadership is ridiculous."
English said the only decider on whether he would remain in Parliament was his own performance. That would be measured by support in caucus and the wider public, as well as the ability to put the Government under pressure.
He said it was not a traditional first-term government and believed Labour would struggle to get agreement within its parties and momentum.
English said National would not be derailed by gossip. He said he had had "stronger indications" in support of his leadership since the change in government.
He said he had not been given any indication from any list MPs that they intended to retire.
The National leader did not believe there was an issue with his deputy Paula Bennett, saying she was a "robust politician" and was used to not being liked by some quarters.
He said one of the reasons National was successful was because it had been a "disciplined and cohesive team". He did not believe there was an issue with discipline.
English said he had not yet decided when to do a reshuffle, but it would take place. It would involve assessing who was performing best in opposition.
He believed the spate of speculation over his leadership could have helped cement it and did not believe it would be raised at National's caucus meeting in Tauranga next week.
National MP Amy Adams said she had "absolutely zero" interest in a change of leadership.
Adams was standing next to English as he fronted to media. She said the party was lucky to have English as its leader and hoped he would stay on for "a long time yet".
English said he did not believe murmuring about his leadership was sparked by his decision not to allow MPs to treat Green MP Chloe Swarbrick's Medical Marijuana Bill as a conscience issue.
While some MPs will be allowed to support that bill, National is otherwise voting against it.
"There may have been some disquiet, but in the end it's a decision the leader makes."
English said National had not traditionally treated votes on drug issues as conscience votes, but he was "quite relaxed" if some MPs wanted to cross the floor.
State of the nation speech
Earlier, in his state of the nation speech, English centred around the strong economic position that New Zealand was in and holding the Government to that high benchmark.
"In the last two years New Zealand has created 245,000 new jobs – more than 10,000 a month. And family incomes have risen ... There is no reason why this shouldn't continue."
The strong position meant that the Government could "muddle along for some time", but the economy needed specific attention, not a mantra of "trees, trains, and trade unions".
He said while Forestry Minister Shane Jones is looking for land to plant 1 billion trees, the Government cancelled the Te Ture Whenua reforms, which he said would have driven more productive use of millions of hectares of under-utilised Maori land.
"Guess where most of it is – in Northland and Bay of Plenty, which have the highest rates of 'nephews sitting on couches', as Mr Jones put it."
English also launched a campaign called Protect New Zealand Jobs to fight the Government's employment relations reforms, which he called a "labour-market experiment" that will hit jobs and give too much power to unions.
"We pledge to do everything we can to try and ensure businesses can continue to create new jobs and increase productivity."
He said plans for industry-wide Fair Pay Agreements was out of step with the "flexibility, agility, resilience and re-skilling" that a modern job market demands.
English said the Government's child poverty reduction legislation had no substance in it, and while the Government's Families Package may have some impact, "according to the Government's own forecasts, for the next four years the money is now all gone".
He again criticised the Government for abandoning National's Better Public Services targets, which he said provided a strategy to reduce poverty.
"The only reason I can see for getting rid of them is because they were introduced by National. Why else would the Prime Minister instruct the public service to stop its focus on reducing the number of children hospitalised for preventable conditions, or who experience a substantiated incidence of physical or sexual abuse? Or increasing the number of vulnerable women who can get good maternity care?
"If the Government won't hold itself to account for making real change to the drivers of dysfunction, then National will do it for them. It is our intention to regularly request official data to track the Government's progress in these areas."
New Zealand First leader Winston Peters said speculation about the National Party leadership was "inevitable".
"Most of them will be there without substance and I think they've got a big problem. The whole front bench line-up has got to be seriously worried about their future."
He said English's speech this morning was "trying to be relevant, but the knives are out now".