The All Blacks are furious after the captain of Super Rugby side Hurricanes snubbed a call-up to the national team because he is signing for Wasps in an attempt to make England's World Cup squad.
The world champions are understood to believe Brad Shields has been given sufficient encouragement by England to reject Steve Hansen's request for him to play against France last week and defect to the Premiership next summer. However, there has been no direct contact between England and Shields, nor has he been given any guarantees.
The place in Hansen's side became available when veteran flanker Jerome Kaino sustained a knee ligament injury but the New Zealand head coach was left stunned when the uncapped Shields, a former All Blacks Under-20s player, revealed that he intended to join Wasps at the end of the next Super Rugby season, which would render him unavailable for New Zealand's 2019 World Cup campaign.
England have long been aware that the 26-year-old qualifies to play for them through his parents, which means he could be fast-tracked into the England squad at the start of next season if Eddie Jones chooses to select him.
At 6ft 4in and 17st 7lb, Shields is a versatile forward who is equally comfortable at No8 and flanker, although the All Blacks privately believe Jones may direct him towards the blindside berth occupied by Chris Robshaw.
The All Blacks were aware of Shields' aspiration to play Test rugby but they are infuriated that he could now be facing them in an England shirt.
Shields was part of the New Zealand Under-20s side who won the world championship in 2011 and who form the basis of the current All Blacks team. Team-mates included Beauden Barrett, Charles Piutau, Sam Cane, Brodie Retallick and Codie Taylor. Long seen as a future All Black, Shields played well for the Barbarians side who drew 31-31 with South Africa, and played for the Hurricanes against the British and Irish Lions last summer.
His signing would be a coup for highly ambitious Wasps, who appear to have beaten competition from Saracens and Leicester, as well as Northampton, who were also interested until they signed former Springbok Heinrich Brussow to fill the gap left by Louis Picamoles' departure.
Shields' switch of allegiance is not without precedent. The England squad boasts two New Zealand-born players - captain Dylan Hartley and Mako Vunipola, while another, Ben Te'o, is injured.