Jeremy Corbyn has described Government claims of record NHS funding levels as a "fake news agenda".
His comments came after he said the way to solve the winter crisis was to put more money into the NHS.
Responding to Government claims it is spending more money than ever on the NHS, Mr Corbyn said: "To misquote Donald Trump, that is a fake news agenda."
"The NHS is stretched beyond belief because of its lack of resources. The Prime Minister told parliament 'we are better prepared than ever for the winter crisis'.
"Two weeks later... we see the reality of it, which is patients being treated in hospital car parks and ambulances."
Speaking after a visit to Lincoln County Hospital, Mr Corbyn continued: "They can't go on to the next emergency because they can't get out of the car park, because they can't safely let the patient leave.
"The pressures are unbelievable. The pressures of patients on trollies in the corridor waiting for a bed. That's pressure, obviously on the patient and their families, but obviously great pressure on the staff.
Speaking about ways of fixing the NHS, Mr Corbyn said: "A lot of it is about money. I've heard of the crisis that was on over the last few weeks.
"Obviously they (the staff) are concerned about the number of older people coming who are suffering from dementia."
Mr Corbyn also said he wants more money put into social care.
He said: "Social care is inadequate. People are coming in because they are desperate.
"Mental health patients are reaching out because they have got nowhere else to go - we have to invest in mental health services and social care."