A recent report from the Grattan Institute recommended that the federal government freeze funding to schools regarded as over-funded and provide more money to schools that are below the Schooling Resource Standard (SRS), the Gonski model's key funding benchmark.
However, speaking with Fairfax Media, Plibersek reiterated that it was "absolutely the right decision" for the Gillard government to make the promise that no school would be made worse off under Gonski.
The current Education Minister, Simon Birmingham
, said he "deliberately" has avoided making the same promise, with cuts to some schools possible when a new funding deal is established for 2018 onwards.
Asked the question of whether funding should be cut to well-off schools and redistributed to struggling ones, Plibersek said, "People find it a compelling thing to talk about but I think it misses the point entirely. You're talking about a very small number of schools."
"If it fixed the problem of there not being enough money on the table from the federal government it would be a different matter but it is a drop in the bucket of the extra money required."
According to the Grattan Institute's report, $215 million is given to a small number of private schools every year, spending it described as "wasteful and inefficient". Among the report's recommendations was reducing the indexation rates for school funding locked into legislation by the Gillard government.
Plibersek added, "I think it was 100 per cent the right decision for us to say no school will lose a dollar.
"If we get sucked into school against school, system against system, state against state, we will still be fighting about this in 10 years' time.
"We are committed that all schools get appropriate funding and that means the poorest schools have the biggest increases in the fastest time."
Regarding comments from Birmingham about inequalities between schools and sectors, Plibersek said he was using "diversion tactics" to distract from the fact he is not funding years five and six of Gonski.
"I'm not going to let him get away with that," said Plibersek.
Labor education spokesperson Tanya Plibersek has said there is no case for cutting funding to "over-funded" private schools and redistributing the money to disadvantaged schools.