The Government is being warned that pressure on the NHS shows little sign of relenting, as ministers come under increasing pressure to respond to the crisis.Top medics described the current situation as “unbearable” and “intolerable”, as both the Prime Minister and the Health Secretary faced calls to address growing concerns about the state of emergency care in the NHS.More than a dozen NHS trusts and ambulance services declared critical incidents over the festive period, with officials citing rising flu cases and the impact of the Covid-19 pandemic among the factors hitting the health service.