There is reported to be more than 55,000 drivers using a loophole to avoid doing the full test.
Under the current system, drivers can renew their permits multiple times, with some going up to 12 years without a full licence.
The Road Safety Authority is planning a major crackdown on the grey area, according to the Sunday Business Post.
John Walsh from The Irish School of Motoring said that it is a cause for concern.
Mr Walsh said: "I'm stunned actually that people, in this day and age, can get away with that, because the fact that they can renew it continuously is alarming, to say the least.
"When you think about it, some of these people we are talking about are going around untested, untried.
"In all cases, they might not be safe and in some cases they might be very unsafe to drive."
