Scotland's children's commissioner has said he may consider legal action over the Universal Credit rollout if it further disadvantages young people.
Bruce Adamson said poverty was the biggest human rights issue facing children in Scotland.
He told the BBC reforms to the benefits systems could be resulting in some children going without basics like a warm home and hot meals.
The UK government said Universal Credit was helping people improve their lives.
A spokesman for the Department for Work and Pensions said the system was "working" and that as a result of Universal Credit people were "moving into work faster and staying in work longer than under the old system".
The controversial measure, which is being rolled out across the UK, brings six existing benefit payments into one.
It faced criticism over claims some people had to wait six weeks for their first payment, contributing to a rise in debt, rent arrears and evictions.
Chancellor Philip Hammond announced changes aimed at speeding up claim times in his autumn budget last month.
Mr Adamson said he was engaging with ministers, from the both the UK and Scottish governments, about the impact the benefit changes were having on the human rights of children and young people.
He called for "political leadership" on the issue, but said he could not rule of the possibility of legal action in the future.
'Basics of life'
In an extended interview broadcast on BBC Radio Scotland on Sunday, the children's commissioner said: "Poverty is the biggest human rights issue facing children in Scotland at the moment.
"And there's a number of issues around the way in which Universal Credit is calculated and how it is paid. But this leads to a much, much deeper issue. We are talking about the rights of children and the right to benefit from social security.
"We are talking about things like having a warm and secure place to live, having regular hot, nutritious meals and also the ability to access things like transport to get to school and to enjoy social and cultural activities that we know are so important to their development."
Asked if there was any prospect of legal redress in Scotland, Mr Adamson said: "While we don't have the Convention on the Rights of the Child within our domestic law yet, we do have the Humans Rights Act which brings in the European Convention on Human Rights and the courts look very closely if a state falls below that minimum standard required, where the state fails to provide those basics of life.
"So certainly if children in Scotland aren't getting those basic things then legal action may be the way to take this forward. But it's not the best way."
He added: "We really need political leadership here and we need to make sure that we are never in a situation where children are going without the basics that they need."
The DWP spokesman said no-one who needed support had to wait six weeks.
He added: "In December, claimants can request an advance of up to 50% of their first payment and a further 50% in January if they need it, repayable over 12 months.
"Universal Credit lies at the heart of our commitment to help people improve their lives and raise their incomes. It provides additional, tailored support to help people move into work and stop claiming benefits altogether."
Speaking on the BBC's Sunday Politics Scotland programme, Brexit Minister Mike Russell said he thought the Scottish government would be "very sympathetic" to potential legal action against Universal Credit if it infringed the human rights of children.
He said: "The approach of the UK government on social security and welfare is truly appalling. It is impoverishing people. It is leading to despair.
"I think anybody who is standing up against that and arguing for a practical resolution, to what are awful, ideological problems being brought by the Tories, I think deserves all the support he can get."
On Saturday, a day of action, organised by the Unite union, saw demonstrations staged at various locations around Scotland protesting against changes to the benefits system.
You can listen again to the extended interview with Children's Commissioner Bruce Adamson on the BBC iplayer.