The 32-year-old will only be available for selection for the series’ second match on Thursday should he make it through Surrey’s County Championship match against Yorkshire unscathed, starting on Friday.
A knee injury has kept Pietersen out since March and he will be itching to prove his fitness and find some form ahead of the Ashes next month.
The right-hander is also anticipated to play against Essex for England in a special warm-up match at Chelmsford, designed to give Alastair Cook’s side a full run-out, starting a week on Sunday.
Pietersen had been expected to play a T20 – but for his county rather than England – and therefore his selection is ahead of schedule.
Selectors have also picked Gary Ballance and Boyd Rankin – both uncapped by England – allowing senior stars such as Stuart Broad and Joe Root a rest following their Champions Trophy final this Sunday.
The announcement also sees a surprise recall for Durham all-rounder Ben Stokes, who was sent home from the Lions’ tour to Australia during the winter for “unprofessional conduct”.
The 22-year-old has played five ODIs and two T20s already for England and will be grateful for a second chance to show off his obvious talents at international level despite his winter’s misdemeanours.
Eoin Morgan will captain the side in the absence of regular captain Broad. The Irish-born batsman has experience of skippering the national team before Christmas when England played India in two T20s.
National Selector, Geoff Miller, said: “We have selected a squad with plenty of T20 experience as well as young players new to the international game.
“With an intense period of cricket coming up we are conscious that we need to manage the workloads of our players throughout the summer and this NatWest series gives an opportunity for players who have performed well in domestic cricket and on the England Performance Programme and with the Lions to step up and test themselves in an international environment.
“New Zealand are a talented limited overs side and with a World T20 competition less than a year away this series gives us a chance to look at a number of different options.”
England Twenty20 squad: Eoin Morgan (Middlesex, capt), Gary Ballance (Yorkshire), Ravi Bopara (Essex), Danny Briggs (Hampshire), Jos Buttler (Somerset), Jade Dernbach (Surrey), Alex Hales (Nottinghamshire), Michael Lumb (Nottinghamshire), Kevin Pietersen (Surrey), Boyd Rankin (Warwickshire), Ben Stokes (Durham), James Tredwell (Kent), Chris Woakes (Warwickshire), Luke Wright (Sussex).