Britain has become the latest European Union member to consider restrictions on social security benefits for future EU citizens.
This leaves Ireland as the only country in the EU which will give workers from the 10 new states - mostly from central and Eastern Europe - equal rights with its own citizens when they join on 1 May.
Blunkett and Blair are concerned about "benefits tourism"
British officials say that Prime Minister Tony Blair and Home Secretary David Blunkett are now considering tighter measures to prevent what they call "benefits tourism."
Estimates for migrant workers who will come to Britain after 1 May vary wildly.
The UK Home Office expects between 5,000 and 13,000 migrants per year from new member states.
But the immigration think-tank Migration Watch says the figure is more likely to be around 40,000.
British officials insist the proposed changes, to be announced some time before 1 May, do not alter their previous pledge to fully open their labour markets to newcomers.
But in effect, tougher tests for housing and income benefits will make life more difficult for those seeking jobs in Britain.
Labour restrictions in new EU
Ireland - fully opening its labour market
UK - opening its market, but considering benefit restrictions
Netherlands - limiting number of migrants
Denmark - giving migrants six months to find a job
Germany and Austria - could impose total bans for up to seven years
Belgium and Finland - could impose bans for up to two years
The rest - still reviewing their policies, restrictions likely
Under the EU's accession treaty, existing members can fully liberalise their labour markets or apply whatever restrictions they want for up to two years after enlargement, without giving any objective reason.
After that, they can extend the restrictions for a further three years, topping up with a further two - leading to a maximum theoretical ban of up to seven years.
However, the longer restrictions can apply only if the countries note serious disturbances of the labour market or the threat of such disturbances.
Germany and Austria, the countries geographically closer to Poland and the other former communist newcomers, took the lead in negotiating such tough terms.
Others, like Britain, Ireland, Denmark, Sweden and the Netherlands, took the opposite line, promising to fully open their labour markets.
But that was back in 2000 and in many countries, parties concerned at a potential influx of migrants have been advocating a tougher line since then.
The European Commission's employment spokeswoman, Antonia Mochan, says they have asked member states twice now for information.
The most recent deadline was last Friday.
"But by Friday, we had only had information from Germany and Belgium, who had already given us the information the last time we asked for it, in November," she says.
"So we would call on member states to please let us know what they intend to do in this area."
Last November, four countries told the European Commission they would introduce labour restrictions for the first two years after accession.
They were Germany, Austria, Belgium and Finland.
Meanwhile, the Netherlands reversed its liberal stance, announcing that a maximum of 22,000 migrant workers from the new member states would be allowed to work there in the first year.
Dutch Finance Minister Gerrit Zalm said last year that the country's labour market should be protected from what he called a flood of cheap labour.
But a recent study by the Netherlands Bureau for Economic Policy Analysis assesses the annual inflow of migrants from central Europe at no more than 5,000 to 10,000.
At the end of last year, Denmark announced the newcomers would not automatically benefit from its generous social security system.
People from central and eastern Europe are allowed to come to Denmark for up to six months, and if they find a job, they can get residence and work permits.
But, as a Danish diplomat put it, you cannot come and pick strawberries for three weeks and then live off Danish welfare for the rest of the year.
Sweden also announced last Friday a review of its labour policy after enlargement, as a result of the tougher stance taken by its EU partners.
"We would be naive, if we were to be the only country welcoming people from eastern Europe to work for peanuts and giving them access to our social benefits," Swedish Prime Minister Goeran Persson said.
A bill setting out the restrictions will be introduced in parliament in the next few weeks.
Swedish trades unions, which originally took a softer line, have also called for a review.
Reaction to far-right
But that is not the position held by the EU-wide European Trade Union Congress, or Etuc.
"I think that some governments are reacting to the far right in some countries and therefore trying to look tougher on migration," their senior adviser Tom Jenkins explains.
"But the reality is that people will move and we would rather people moved legally rather than illegally, so that proper standards can be applied to them."
The European employers' confederation, Unice, says that many workers from central and eastern Europe are already in the EU - some 850,000 people, or 0.2% of the EU population.
Neither Unice nor Etuc - nor indeed the European Commission - expect a further mass inflow of cheap labour from Poland or from any other new member state.