NHS Scotland will not be able to maintain its level of service unless it receives more funding, the British Medical Association (BMA) has warned.

The country's health service has been under pressure in recent weeks amid an increase in flu that led to patients waiting hours to be seen at accident and emergency (A&E) wards during the festive period.

One health board, NHS Lanarkshire, had to ask their office staff to volunteer to clean dirty hospital wards and GP practices.

Elective and non-urgent operations were cancelled for a number of days at Monklands, Hairmyres and Wishaw hospitals last week in a bid to free up medics.

BMA Scotland chairman Dr Peter Bennie rejected claims that winter crises are "inevitable" and instead blamed a lack of planning and resource funding from the Scottish Government.

He said: "Instead of gratitude, we need a long-term, sustainable plan that closes the growing gap between resources, in particular finances, and the demand for services.

"And we must not simply dismiss this as the inevitable increase in pressure that winter brings. This time of year can bring the challenges the NHS faces on a daily basis into a sharper focus.

"But ultimately, there is simply not the funding or plans in place to go on as we are, regardless of what season we are in."

He added: "The BMA believe that multiple targets, an ageing population and the funding gap are creating a vicious circle, stretching the system and the workforce beyond their means.

"In winter, that results in the type of rapid deterioration of services that we have seen over recent days. But over the course of the rest of the year it also means the ongoing eroding of standards, care and services. Patients deserve better."

Health secretary Shona Robison said NHS Scotland is benefiting from record staffing and funding levels.

She said the Scottish Government aims "to go further" and will increase the health service's budget by £2bn by 2021.

Robison said: "Health boards have worked to put in place robust winter contingency planning arrangements, which they've demonstrated in their response to exceptional winter pressures.

"Staff right across Scotland should be thanked for their hard work and dedication throughout this time.

"Flu rates in Scotland doubled in December and there was a 20% increase in A&E attendances leading up to Christmas."

She added: "During Christmas week, the Scottish Ambulance Service reported an almost 40% increase in the number of calls on Hogmanay alone, and NHS 24 received more than 45,000 calls in the four days over Christmas - almost double the number of calls in the same period last year."