Fekitoa, who turns 22 early next month, has been the surprise package of the Super 15 season.
He scored an outstanding try for the Highlanders in the surprise win over the Sharks at the weekend, beating up to half a dozen players in a 55m run to the tryline.
It was the latest in some dazzling action from the young Tongan, who has played every game for the Highlanders so far this season.
Fekitoa is in his first season for the Highlanders after a disappointing season with the Blues last year when he made the squad but did not get on the field for a single minute.
Highlanders general manager Roger Clark confirmed Fekitoa was signed until the end of next season.
''Part of the deal that we signed him is that we had him for two years. He had signed a three-year deal with the Blues and when we took it over we wanted to have the two years left,'' he said.
''We didn't want it to be just a one-year deal. We didn't want to sign him and then lose him after just one year.
''We had been watching him, even in club rugby, and had our eye on him. So when he became available we went for him.''
Fekitoa was surplus to requirements at the Blues as the Auckland-based franchise inked deals with the likes of Ma'a Nonu and Benji Marshall.
With too many players on the books at the end of last season, Blues coach Sir John Kirwan was forced to move a couple of players on and ended up getting rid of Fekitoa and Marty McKenzie.
''We had been watching him [Fekitoa] for a while and so when he became available we moved in. But to be fair, most of the other teams had their full allotments by then.''
Fekitoa grew up in Tonga and came to New Zealand in his late teenage years, on a rugby scholarship to Wesley College.
One of 14 children, he has just fulfilled the residency requirements meaning he can now play for the All Blacks.
With his eye-catching performances this season, Fekitoa is a chance to wear the black jersey in the June series against England, although his efforts over the next few games will be key to wearing the national colours.
Clark said negotiations were continuing with All Black halfback Aaron Smith.
Smith's contract with the Highlanders comes to an end at the finish of this season and Clark said the Highlanders would obviously want to keep the 25-year-old who has played 26 tests.
Negotiations continue through the season with players and many have multi-year deals.
One position the Highlanders may have to look at is lock - Jarrad Hoeata is heading to Cardiff at season's end, Brad Thorn has suffered a serious bicep injury and the future is uncertain for Josh Bekhuis, whose contract comes to an end this season.
Meanwhile, Taieri prop Aki Seiuli is training with the remaining Highlanders back in Dunedin this week, as prop cover.
Craig Millar injured his shoulder in the win over the Sharks and is due back from South Africa today, along with injured winger Patrick Osborne, who has a high-ankle sprain. Matias Diaz has travelled to South Africa as front-row cover.
Miller and Osborne should have scans on their injuries today.
