The head of Theresa May's policy unit has defended changes to disability benefits by suggesting the money should go to "really disabled people" rather than those who are "taking pills at home, who suffer from anxiety".
George Freeman said reforms to personal independence payments (PIP) were needed to roll back the "bizarre" decision of a tribunal, which said claimants with psychological problems who cannot travel without help must be treated like those who are blind.
The tribunal also said claimants who need support to take medication should be assessed the same way as those managing therapies such as dialysis at home.
Responding to the upper tribunal rulings on Thursday as Westminster's attention was on two by-elections, disabilities minister Penny Mordaunt said she was reforming the payments to "restore the original aim of the benefit" to make sure the most needy were given support.
Ms Mordaunt said no claimants would see a reduction in the amount of PIP previously awarded by the Department for Work and Pensions (DWP).
But Labour said the Government's equality assessment showed 160,000 would miss out on money that was "rightfully" theirs.
Mr Freeman, the head of the Number 10 Downing Street policy board, said it was the right decision.
He told Pienaar's Politics on BBC 5 Live: "These tweaks are actually about rolling back some bizarre decisions by tribunals that now mean benefits are being given to people who are taking pills at home, who suffer from anxiety.
"We want to make sure we get the money to the really disabled people who need it."
Challenged on his assessment of anxiety, Mr Freeman said: "I total understand anxiety and so does the Prime Minister. We've set out in the mental health strategy how seriously we take it.
"My point was that these PIP reforms are partly about rolling back some frankly bizarre decisions in tribunals which have seen money that should go to the most disabled spent on people with really much less urgent conditions."
Shadow chancellor John McDonnell said he was "furious" about the changes, which he said would amount to a £3.6 billion cut.
He said Labour would press the Government to reverse the changes in next month's Budget.
"The Tories are trying to say they're no longer the nasty party, they are the nasty party... and they are the party of spin and triangulation again," he told the programme.
"While Theresa May was parading around Copeland (for the by-election), what was happening was that they were cutting benefits to some of the most vulnerable in our society.
"These are people, many of them with severe disabilities, who are going to be trapped in their homes.
"We are going to have a Labour Party campaigning out there to reverse this. This is cruelty in the extreme."
Tory MP David Burrowes, who rebelled over separate cuts to disability benefits last year, signalled he would back the changes.
"It is always a difficult judgement call to make about who should receive the highest PIPs when all claimants are vulnerable with challenging needs," he said in a statement.
"However, PIPs need to fulfil their original aim, which is to support those who face the greatest challenges in everyday life and be financially sustainable.
"Once the tribunal had widened the net, unless the Treasury is to find £3 billion, there will be future claimants with challenging needs who miss out."
Reacting to Mr Freeman's comments, Labour MP Louise Haigh tweeted: "They know this will affect ppl w/ PTSD, dementia, schizophrenia, seizures.
"Tories in the gutter trying to shame those in desperate need".
Mr McDonnell later called on Mr Freeman to apologise.
He tweeted: "This is an insult to disabled people. (George Freeman) should apologise immediately or Theresa May should make him."