Iain Duncan Smith quits over planned disability benefit changes

Work and Pensions Secretary Iain Duncan Smith has resigned citing pressure to make cuts to disability benefits.

It comes after mounting controversy over £4bn of planned cuts to Personal Independence Payments, expected to affect 640,000 people.

Mr Duncan Smith said the cuts were "not defensible" within a Budget that "benefits higher earning taxpayers".

Earlier, a government source indicated the changes were going to be "kicked into the long grass".

The planned changes apply to the formula the government uses to calculate the daily living component of PIP, which will replace Disability Living Allowance (DLA) and come into effect in January 2017.

Mr Duncan Smith said they were a "compromise too far".

"I am unable to watch passively whilst certain policies are enacted in order to meet the fiscal self-imposed restraints that I believe are more and more perceived as distinctly political rather than in the national economic interest," he said in his resignation letter.

"Too often my team and I have been pressured in the immediate run up to a budget or fiscal event to deliver yet more reductions to the working-age benefit bill.

"There has been too much emphasis on money-saving exercises and not enough awareness from the Treasury, in particular, that the government's vision of a new welfare-to-work system could not be repeatedly salami-sliced.

"It is therefore with enormous regret that I have decided to resign."