ANY children kidnapped in an overseas adoption racket will likely have to be returned to their families, federal Opposition Leader Brendan Nelson says.

At least 30 children adopted in Australia may have been stolen from their parents by a child trafficking ring operating in India between 1998 and 1999.

The Queensland Government and Indian investigators will soon begin working together to investigate the claims.

"Let us hope that the inquiry, in fact, does not find that children have been effectively kidnapped," Dr Nelson said.

"But if they have, then we will have a moral responsibility to do the right thing.

"And the right thing, we would expect in most cases, will be to look at returning them to their rightful families."

Dr Nelson rejected suggestions Canberra should wrest control of adoption legislation from the states.

"I don't think that we should have knee-jerk responses that suggest that the Commonwealth should automatically take it over.

"So let's just wait until we get the outcome of the inquiry before people start to say: 'Well, if the Commonwealth takes it over that will solve all the problems'.

"Generally speaking, Government is the problem, not the solution."