The UK might see as much as 300,000 new workers from Bulgaria and Romania if the country allows unrestricted access when the two countries join EU.
That was suggested by Migrationwatch as cited by the Daily Telegraph on Monday.
While Sofia and Bucharest are looking to Tuesday's monitoring report by the European Commission, the Migrationwatch chairman has warned that the UK cannot absorb unlimited immigration on a small crowded island.
"The arrival of very large numbers of Romanian and Bulgarian workers in the UK is a distinct possibility," Sir Andrew Green has said, insisting that the government should not apply its previous policy on European immigration.
The UK should wait for the decisions of the other major European countries before granting unlimited access, Green advised.