The union is backing an amendment brought by MP Yvette Cooper to the Immigration Bill ​that would ensure many more staff – such as social care workers, hospital cleaners, healthcare assistants and porters – would not have to pay up to £3,000 to remain working on the Covid-19 frontline.

A campaign launched by UNISON urging people to write to their MP to get the Bill changed coincides with the publication today (Monday) of a Home Affairs Select Committee report​, which also calls for a visa scheme extension.

Only around 3,000 NHS workers – whose visas were due to expire before 1 October – currently qualify for the free extension announced in April by the Home Office.

UNISON says many more are having to face the costly and stressful process of applying because they are not eligible under the scheme.

They include care support worker Akeem Lawall who has been working up to 60 hours a week looking after vulnerable people throughout the pandemic in a care home.

The 37-year-old earns just £9.50 an hour but will have to pay to replace his visa when it expires in September this year, despite being classed as an essential worker.

Akeem, who came to the UK from Nigeria in 2016 and is married with two children, says: “I want to continue in my job caring for people.

“The visa is a huge cost though that I’ll struggle to pay given my wages – I don’t know how I’ll find the money.”

UNISON is also calling on the government to grant key workers who have been on the Covid-19 frontline indefinite leave to remain.

UNISON assistant general secretary Christina McAnea said: “It’s deeply unjust that thousands of care workers and NHS staff don’t qualify for this free scheme.

“It’s a costly process reapplying and one that’s stressful at the best of times, let alone during a pandemic.

“Many migrant workers are in a precarious position with their visas up for renewal during the crisis. They’re on the frontline looking after us – we must look after them too.​”