The United Nations is urging changes to the Turnbull government's proposed overhaul of citizenship laws, flagging concerns they may fall foul of international conventions.
The UN High Commissioner for Refugees (UNHCR) is among nearly 500 individuals and organisations to make submissions to a Senate committee investigating the citizenship crackdown.
Its concerns centre on tougher English language requirements, longer waiting times, blocking applications based on criminal histories and potential consequences for abandoned children.
The government argues its changes will ensure aspiring citizens demonstrate an allegiance to Australia and willingness to integrate and contribute, while showing a commitment to the nation's laws and values.
But the UNHCR believes the changes are not necessary to integrate refugees and stateless people into Australia, and will disproportionately affect their chances of acquiring citizenship.
It recommends "basic" knowledge of English be maintained as the standard rather than shifting to "competent", or instead that humanitarian entrants are exempted from the hurdle.
"Refugees are less likely than other migrants to move to countries where they already have some cultural, linguistic or economic links, and most come from non-English speaking countries," its submission said.
The UNHCR wants criteria for attaining citizenship expressly set out in legislation, and urges against including statutory requirements for community integration.
The Turnbull government also wants to increase the minimum permanent residency period from one year to four, but the UNHCR says this too will disproportionately affect refugees and stateless people.
Many asylum seekers wait years before being granted permission to apply for protection, and spend longer still on temporary visas before being eligible to apply for citizenship.
The UNHCR estimates a significant number of refugees are likely to wait more than 15 years before securing citizenship, urging parliament to reject the extended wait times altogether.
It wants a proposed amendment relating to abandoned children struck out, fearing it may leave some kids stateless, therefore breaking Australia's obligations under international conventions.
The UNHCR has also asked senators to exempt stateless people from proposed changes around blocking citizenship by descent based on criminal offences, saying this too could break international conventions.
The Senate committee investigating the legislation is due to report by September 4.