Immigrants from Eastern Europe must be kept out of Britain – out of fairness to their home countries, a Birmingham MP said.
Gisela Stuart (Lab Edgbaston) said immigration from Bulgaria and Romania must be restricted to prevent those nations suffering a brain drain. Britain attracted "the best, the brightest" workers from overseas, she said.
But another Midland MP, Mark Pritchard (Con The Wrekin), warned Eastern Europeans were causing unemployment in the region.
The MPs were speaking after it emerged 60,000 immigrants, roughly equal to the entire population of North Warwickshire, have already come to the West Midlands from Eastern Europe.
The Home Office originally claimed only 5,000 to 13,000 people would migrate to the whole of Britain each year.
The Government is now bracing itself for a fresh influx of immigrants when Bulgaria and Romania join the European Union next month.
Birmingham MP Liam Byrne (Lab Hodge Hill), a Home Office Minister, warned in a leaked memo that organised criminal gangs from Bulgaria would use the opportunity to set up operations in the UK.
Bulgarians and Romanians will be temporarily banned from working in the UK unless they have specific skills or are self-employed, but they will be free to enter the country as they wish.
Ms Stuart, who was born in Germany and moved to the UK in 1974, said: "May I put forward another argument concerning Romania and Bulgaria? By definition, the people who leave their own country are often the best, the brightest and those with the most get up and go.
"Cannot those countries ill afford to lose those people to the bright lights of other countries, and might not our policy in fact be doing them a favour?"
MP Mark Pritchard (Con The Wrekin) warned: "Many of those people are contributing legitimately to our economy and have brought skills that we need. However, this needs to be seen in the context of unemployment, which is at a seven-year high.
"Unemployment is going up and we have an inflow of economic migrants, so more people are chasing fewer jobs.
"We also see wage deflation in some areas of the economy, certainly in the agricultural sector in Shropshire, Herefordshire and other parts of the West Midlands. If we are not careful, the very good community relations that this country has enjoyed over generations, for hundreds of years, could inadvertently be undermined."
Speaking in the same debate, Daniel Kawczynski (Con Shrewsbury) accused other nations of breaking EU rules and gaining an unfair advantage against British industry.
Mr Kawczynski, whose family moved to Britain from Poland in 1940, said: "One of the problems and frustrations that we face is that we in Great Britain play by the Queensberry rules, we do what the EU tells us to do and we are compliant, unlike our partners in the EU who repeatedly break agreements and cheat.
"An example of that is the Irish. The Irish have recently given their dairy farmers #300 million in illegal subsidies."
He added: "We are going to give #8 billion of taxpayers’ money to help the Romanians and Bulgarians with their agriculture, so that their systems become comparable with ours.
"That money is being sent to foreign countries. Our own dairy farmers in Shrewsbury are going out of business day after day, while we prop up the Irish, the Romanians and the Bulgarians."
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