She is to claim that mass migration leads to the undercutting of the wages of some low-paid workers and is forcing thousands of others out of work altogether.
May will use her speech on Tuesday to renew her 2010 pledge to cut net migration to below 100,000 by telling the Conservative party conference that – while there are benefits from selective and controlled migration – the net economic and fiscal benefits are close to zero.
Britain must fulfil its moral duty to refugees fleeing for their lives, she will say, but that does not mean letting in millions from poorer countries who would love to come to the UK, and there must effective immigration limits and controls on who enters.
The home secretary has a monumental task in restoring public confidence in her pledge to end the era of mass migration to Britain. During her five years in office, net migration has risen to a record 330,000 a year despite attempts to stem the flow.
She has even recently proposed closing the door to migrants from other EU countries who do not already have a specific job offer in Britain. David Cameron has also vowed to use EU renegotiation to ensure EU migrants cannot claim benefits in Britain for their first four years.
May is to say that people on both extremes of the debate – “from the anti-immigration far right to the open-borders liberal left” – conflate refugees in desperate need of help with economic migrants who simply want to live in a more prosperous society.
“Their desire for a better life is perfectly understandable, but their circumstances are not nearly the same as those of the people fleeing their homelands in fear of their lives … While we must fulfil our moral duty to help people in desperate need, we must also have an immigration system that allows us to control who comes to our country.”
She will also say: “When immigration is too high, when the pace of change is too fast, it’s impossible to build a cohesive society. It’s difficult for schools and hospitals and core infrastructure like housing and transport to cope.
“And we know that for people in low-paid jobs, wages are forced down even further while some people are forced out of work altogether.
“Now I know there are some people who say, yes there are costs of immigration, but the answer is to manage the consequences, not reduce the numbers. But not all of the consequences can be managed, and doing so for many of them comes at a high price.
“We need to build 210,000 new homes every year to deal with rising demand. We need to find 900,000 new school places by 2024. And there are thousands of people who have been forced out of the labour market, still unable to find a job.”
May will say she accepts that migration does fill skills shortages, but not every person coming is a skilled electrician, engineer or doctor.
She will claim the evidence from the OECD and a House of Lords economic committee shows: “While there are benefits of selective and controlled immigration, at best the net economic and fiscal effect of high immigration is close to zero.
“So there is no case, in the national interest, for immigration of the scale we have experienced over the last decade.”
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