Closing the gap programs to fix Aboriginal disadvantage will be undermined if indigenous languages aren't preserved, the Commonwealth Ombudsman says.
The man charged with overseeing the Northern Territory emergency response and closing the gap programs, Allan Asher, said government departments were not always using indigenous language interpreters when they should be.
He said these services can sometimes be difficult to obtain.
"Without interpreters and proper regard to the language barriers that indigenous Australians face, service delivery can be misdirected and damaging," he said in his submission to the House of Representatives inquiry into language learning in indigenous communities.
"People can be excluded from and alienated by the very programs designed to assist them."
Mr Asher said urgent action was needed to preserve languages.
"If indigenous languages are not preserved and then taken into account in service delivery to indigenous Australians, many closing the gap initiatives will be undermined."
He said a national framework was needed to increase the recruitment and retention of indigenous language interpreters.
Mr Asher said his office had received many complaints about the changes in the Northern Territory education system that have cut time spent teaching indigenous languages.
He said one complainant had threatened to take children out of school over the issue.
Another letter writer told the ombudsman the decision had cut community involvement in the classroom.
"Warlpiri elders used to come to the school and teach the children in Warlpiri, this has stopped and the white people are pushing the Warlpiri aside," the letter writer said.
Margaret Opie, who has decades of experience teaching English in indigenous communities and in Indonesia, said it was vital Aboriginal kids were taught in bilingual classrooms.
"I am convinced that English literacy comes easier to those who are literate in their own language," she said.
She said in Java students learn to read and write in Javanese until they are about nine years old.
Then they learn Indonesian Bahasa followed by English for tourism and commercial purposes.
"Standards of literacy are quite high and students develop practical use of English very quickly," she said in her submission.
Ms Opie said children needed to be able to perceive their own language in written form in order to appreciate English as a written and spoken language.
The Eastern States Aboriginal Languages Groups said greater appreciation and learning of indigenous languages could improve the self-worth of young indigenous people who are often caught up in the justice system.