Diane Abbott told her party’s annual conference in Liverpool on Tuesday that leaked sustainability and transformation plans (STPs) looked increasingly like vehicles for cuts.
The STPs, she said, were health secretary Jeremy Hunt's 'answer to the £22bn funding gap'
'Some of these plans may be a good idea in principle,' she said. 'But increasingly these STPs look like a vehicle to drive through cuts and closures.
'Where these STPs are purely about cuts Labour will fight them all the way.'
Leaked STPs obtained by campaign group 38 Degrees have included plans to cut the number of GP practices. Transformation plans in east London first revealled by GPonline last month include proposals to consolidate practices to serve populations of 10,000 or more.
Ms Abbott said there was already a move in the NHS towards restricting access to non-urgent operations.
'This rationing by stealth will affect the poor, the elderly and the vulnerable most severely,' she said.
The shadow health secretary reiterated Labour's commitment to 'halting and reversing the tide of privatisation and marketisation of the NHS', and to repeal the 2012 Health and Social Care Act.
'This means returning our NHS to what it was originally conceived as: a publicly owned, publicly funded, publicly accountable, universal service,' Ms Abbott told the conference.
The east London MP pledged the party's support for junior doctors in their fight against the government's contract imposition.
Junior doctor contract
'Let there be no doubt Labour stands with the junior doctors,' she said.
Jeremy Hunt had mishandled the dispute and vilified the juniors and their union, said Ms Abbott, treating them as 'the enemy within'.
'But it is absolutely clear to the public that the responsibility for this dispute lies at the door of Jeremy Hunt himself.'
The dispute, she added, demonstrated the 'collapse of morale amongst NHS workers as a whole'.
Ms Abbott promised that a Labour government would restore student bursaries for nurses, midwives and other healthcare workers, which have been scrapped by the government.
She also pledged to end the private finance initiative (PFI) in the NHS by refusing to sign another public-private finance contract if Labour takes power. The party would also set up a PFI monitoring unit to support NHS providers to to hold contractors to account.
'Our NHS,' she said, 'is not there for investment bankers and private equity specialists to rake off profits.'
Ms Abbott said the health and care systems were dependent upon tens of thousands of EU workers. 'We need to be clear that an end to freedom of movement could be a disaster for the NHS and social care. And we need to demand assurances from the government about the EU workers already here.'