The UK is set to deny working visas to low-skilled migrants from next year.
The UK Home Office said it would introduce a new post-Brexit system based on points, with EU and non-EU nationals treated equally.
Under the new system, anyone coming to the UK for work must already have a job offer and speak English.
The UK Government estimates that 70% of EU nationals currently working in the UK would be refused a visa if applying under the new system.
British ministers have claimed the system will make it easier for higher-skilled workers to get visas; however, critics have warned that the plan could be an “absolute disaster” for the UK social care sector.
There are also concerns over the impact on British farming.
On Sky News, UK home Secretary Priti Patel said the new system would see the UK taking back control and ending free movement.
She said it would see a reduction in migration – but stopped short of saying by how much.
The Confederation of British Industry (CBI) warned that the care, construction, hospitality, food and drink sectors could be most affected by the changes.
Christina McAnea from Unison, which represents care workers, said: "These plans spell absolute disaster for the care sector.”
“Companies and councils can't recruit enough staff from the UK so we have to rely on care workers from elsewhere. But even with these migrant employees, there are still way too few care workers to meet demand.”
The Royal College of Nursing also said the proposals would “close the door” on lower-paid healthcare workers, while the UK Homecare Association warned it could mean more people “waiting unnecessarily in hospital or going without care.”
Labour's shadow home secretary Diane Abbott said: “Talking about immigrants as if they're a problem is not the sort of leadership that government ought to offer.
“The Labour Party celebrates the contribution of immigrants.
“We want a fair system; we won't play the Tories' dog-whistle politics.”
Liberal Democrat home affairs spokeswoman Christine Jardine said the proposals were based on “xenophobia” and not the "social and economic needs of our country.”