Britain has prepared its military to step in and drive ambulances on Wednesday when more than 10,000 paramedics and call handlers strike, as the standoff over pay between government and healthcare workers escalates.

Double-digit inflation has sparked industrial action across the British economy as workers balk at the prospect of declines in real wages at a time when the cost of food and energy is rising and the economy is sliding into a recession.

That has already hit Britain's publicly funded healthcare system, with nurses striking last week for the first time in more than 100 years and due to walk out again on Tuesday over demands for a pay rise of 5 percent above inflation.

In some areas of the country ambulance drivers, call handlers and support staff will walk out on Wednesday, marking a more visible and potentially more dangerous phase of the industrial unrest that has also crippled the rail network and disrupted pre-Christmas postal services.

"There will be impacts on patients as a result of the strike action," health minister Steve Barclay said.

While ambulances will still be sent to life-threatening emergencies, patients with less serious conditions are being advised to make their own way to hospital.

In response, the government has turned to its armed forces, putting 600 drivers and 150 logistical staff on standby.

Both sides in the pay dispute now say it is up to the other to make the first move.

The government will not discuss increasing the 4 percent it gave all health service staff in July on the recommendation of an independent pay review. Worried about tight budgets and fuelling inflation, it says big wage rises would be irresponsible.

Ambulance workers have not set out their exact demands but UNISON union leader Christina McAnea said there was a risk staff would leave the service for better paid jobs and called the government's approach to negotiations "completely intransigent."

"Seriously, there's no trust left between us and the government," she told BBC radio.

(Cover: Ambulance teams work in the Accident and Emergency zone of St Thomas' Hospital in London, England, December 19, 2022. /CFP)