Sears, who was a travelling reserve for the T20 World Cup last year, recently played his first game since April having returned in the Super Smash following injury and is in line for his ODI debut having played one Test and 17 T20Is. O'Rourke has impressed across formats early in his international career and has been especially eye-catching in Tests.

Smith, meanwhile, will bring lower-order power with the bat and bustling seam bowling.

"We've been a little conservative in Ben's return to play, but we always had an eye that we thought he would be part of this Champions Trophy squad," Stead said. "He's one of those guys, when you look at places like Pakistan, that pure speed is something that you're looking for, and he certainly has that. A young tearaway is always nice to see, and very excited to have him in the squad."

Stead was confident Sears would hold up fine, match-fitness-wise, after his return from injury.

"Ben's been bowling a lot over the winter still," he said. "He's been in and around our Test squads before he had that injury, so we're very confident that he will be where he needs to be."

Ferguson, Williamson and Conway face T20 league logjam

The same squad will take part in the ODI tri-series in Pakistan ahead of the Champions Trophy, which will also feature South Africa. Duffy has been named on standby for that series, if Ferguson is not available for those games due to the ILT20. There will also be a tight turnaround for Kane Williamson and Devon Conway who are at the SA20.

The final of the SA20 will be played on February 8, with the ILT20 decider the following day. New Zealand will play Pakistan on February 8 in their first game of the tri-series followed by South Africa on February 10. They then have a warm-up match against Afghanistan on February 16.

Stead said New Zealand were looking to have Ferguson, Williamson and Conway play at least two matches - including the warm-up - to ready themselves for the Champions Trophy. "Those three guys, they're world-class players for us. So Kane, Devon and Lockie will join our squad - they could be there at the very start of the tri-series, [or] it might be a couple of days later."

Mark Chapman and Will Young have earned spots while spin-bowling allrounder Michael Bracewell has also been included.

New Zealand will play the tournament opener against Pakistan in Karachi. Their second match is against Bangladesh in Rawalpindi before they travel to Dubai to face India.

"We like to stick to the same team once we've picked it but it will probably be very conditions-dependent," Santner said. "Karachi could play a lot different to Rawalpindi, and again in Dubai. With the short nature of the tournament, if you're happy with your XI, you want them to be out there and perform for the full three games. But we're open to changes depending on conditions. You need to play your best team on what's in front of you, and conditions will probably dictate it."

New Zealand squad for Champions Trophy and Pakistan tri-series

Mitchell Santner (capt), Michael Bracewell, Mark Chapman, Devon Conway, Lockie Ferguson, Matt Henry, Tom Latham, Daryl Mitchell, Will O'Rourke, Glenn Phillips, Rachin Ravindra, Ben Sears, Nathan Smith, Kane Williamson, Will Young

0700 GMT The story was updated with Stead and Santner quotes.