Senedd members pressed Wales' first minister about the Labour UK Government's plans to slash spending on welfare by £4.8bn a year by the end of the decade.
Plaid Cymru's Llŷr Gruffydd questioned Eluned Morgan about reforms announced in this week's spring statement during a scrutiny committee meeting on Friday.
He said: "Disabled people are particularly going to be hit by this. Three million families are going to lose out financially, a quarter of a million people are going to be thrown into poverty, 50,000 of those children. Why did you support the changes?"
"Hang on, let's be clear," the first minister responded. "This is a non-devolved area, so I am not accountable for what goes on in relation to the welfare situation."
"What I do know is that it would be a good thing to have more people in work in Wales, our employment is not nearly as good as some other countries."
'Poverty trap'
Baroness Morgan told the committee she was yet to receive a response to a letter she sent Liz Kendall, the UK work and pensions secretary, seeking clarity on the impact in Wales.
"I don't think trapping people in welfare poverty is a great position either," she said. "I think we've got to support people to get out of the poverty trap."
Pressed on whether she supports the changes outlined by the UK chancellor, Baroness Morgan replied: "I'm yet to get a firm understanding of how that will impact on Wales and until I'm clear about the impacts I want to reserve my position in relation to that."
Mr Gruffydd countered: "Well, that's very different to what the secretary of state said because she's on record as saying 'the first minister wrote supporting the reforms and I was really pleased to see backing for those reforms'. So is she wrong?"
The first minister, who has been in post for about eight months, repeated her position, warning of "huge, unsustainable" increases in the number of people claiming benefits.
'Armies of people'
Asked about a phone call with No 10 to raise her concerns, Baroness Morgan said she could not remember who she spoke to but it was not prime minister Keir Starmer.
"You can't even tell us who you spoke with about it?" Mr Gruffydd asked. "You're the one who was on the phone but you're not sure who you talked to?"
Baroness Morgan told the committee she speaks to hundreds of people every day and has "armies of people" who set up meetings, saying she would provide a list of names.

Mr Gruffydd pressed the first minister on her claims to have influenced welfare reforms, asking precisely what she persuaded the UK Government of.
She responded: "I set out, gave them a sense of the concentration of the numbers of people who are on, in particular, sickness benefits in some of our communities."
She added: "I'm told afterwards that that did help to inform their decision making."
'Floundering'
Mr Gruffydd warned the reforms will have a disproportionate impact on people, putting a huge strain on services and leaving Wales "floundering to pick up the pieces".
Baroness Morgan reiterated that she is reserving her judgement, saying: "I just think it's fascinating that I'm constantly asked about what's happening in Westminster. Hold me to account for things I'm responsible for."
Mr Gruffydd said: "But you're the one who's been talking about a 'partnership in power' between Labour in Cardiff and Labour in London."
The first minister pointed to £1.6bn extra for public services in the Welsh Government's 2025/26 budget as an example of the influence on colleagues in Westminster.
The Conservatives' Mark Isherwood warned autistic and other neurodivergent people are terrified by the announcement and the implications for their lives.
'£500 better off?'
Andrew Jeffreys, director of the Welsh treasury, said the only prior engagement on the reforms was a conversation finance secretary Mark Drakeford had on the morning of the statement.
Mr Gruffydd raised the Welsh Government's written response to the spring statement, which claimed households will be £500 better off on average by 2030.
Asking how ministers arrived at the figure, he said: "Yet, the Resolution Foundation has said, because the benefits cuts fall disproportionately on lower-income households, it'll mean an average annual loss of £500 by 2030 for those in the poorest half of the population."
Baroness Morgan said: "I don't think there is a contradiction there...the average family will be £500 better off. I recognise that there will be families who will be impacted."
She reiterated: "Well, look, as I say, we're days into knowing this situation. We still don't have a clear picture of how it's going to impact on us."

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