Mr Wakefield said they were "very tiny little girls" and he was not willing to let the man drive on with them unrestrained.
He called colleagues at the Warkworth police station, asking them to go to his home and pick up his own children's car seats.
He stayed with the man until the seats arrived, then fitted them into the car and made sure the girls were strapped in before they left the traffic stop.
Mr Wakefield followed the man to Manukau and when he was home safely collected his car seats and went home.
By then his shift had finished and he got home quite late.
"I couldn't really see any other choice as he had no other car seats available," he said.
Mr Wakefield said his main priority was "to get those little kids home safely, at least that night".
Waitemata road policing manager Inspector Trevor Beggs commended Mr Wakefield for going the extra mile to ensure the girls' safety. "Instead of just writing out a ticket Constable Wakefield realised this chap had kids of a very similar age to his own," Mr Beggs said.
"He had a bit of empathy, a bit of Christmas spirit and he got his own car seats from his own vehicle and fitted them into the chap's car."
Mr Wakefield gave the driver an infringement notice for his speeding and for not having his daughters restrained.
"He did have to issue an infringement to the motorist but made sure the precious cargo got home safely for Christmas," said Mr Beggs.
"It was nice of him to go the extra mile. It was all about getting those little girls home safe."
Under New Zealand law, all children under 7 years of age must use an approved child restraint appropriate for their age and size.
Children aged 7 must be secured in a restraint if one is available in the vehicle.
Ann Weaver from Safe Kids said the incident was a good chance to remind parents and drivers of their duty to protect young passengers.
"Those children should have been in their own car seats, correctly installed from the beginning," she said.
She said motor vehicle crashes are the number one cause of death among children ages 1 to 19 in New Zealand.
Of those children aged 12 and under who died in vehicle crashes in 2011, 31 per cent were unrestrained.