NHS trusts fear that the effects of strike action by ambulance workers today will have a greater impact on services.

Life-threatening situations, such as cardiac arrest will continue to be responded to by ambulance but less urgent calls may to have to wait longer than usual.

Today’s walk-out is set to involve more staff and last longer than previous action with a further strike scheduled for 23 January.

Miriam Deakin, the interim deputy chief executive and director of policy and strategy at NHS Providers, said: “The picture will vary across the country but with more staff expected to strike this time, the NHS is in an even more precarious position.

“Since the last strikes, delays transferring patients from ambulances to hospitals have got worse as pressure across the whole of the NHS increases.

“Trust leaders are working hard to minimise the impact on patients and to support staff during the industrial action but they are braced for another day of significant disruption and knock-on effects.

“We understand completely why overworked ambulance staff have been driven to strike. It’s deeply disappointing that talks between the government and unions have not averted more strikes. Only serious pay negotiations promise to do that.”