The Bulgarian ambassador has told ITV News there should be no panic about an influx of Bulgarians as many of them who want to work in the UK have already arrived in the country.
Figures released by the Office for National Statistics suggest the number of Romanians and Bulgarians working in the UK has risen by more than a quarter in three months.
Ambassador Konstantin Dimitrov said, "I think it is unnecessary for the simple reason that most of those who want to come here have already done so".
ITV News correspondent Juliet Bremner reports:
Migration Watch UK says the rise in the numbers of Romanians and Bulgarians making their way to Great Britain will rise to 50,000 a year once restrictions on the types of work they can do are lifted.
The government has refused to give a figure for how many workers from Romania and Bulgaria it expects to arrive in the UK.
The number of Romanians and Bulgarians working in the UK has risen by more than a quarter in three months, according to new figures from the Office for National Statistics.
- 141,000 Romanians and Bulgarians were employed between April and June an increase of 26% on the previous three months.
- 112,000 Romanians and Bulgarians were employed between January and March.
Laws restricting the types of work undertaken by migrants from these two countries will be lifted from the start of next year.
British citizens are being separated from partners and children from outside the European Union (EU) by new migration rules that are "causing anguish for families", a group of parliamentarians has found.
A breast-feeding mother separated from her British baby was among the cases the All-Party Parliamentary Group (APPG) on Migration heard during its inquiry into the rules that came into force on in July last year.
A minimum earnings requirement for Britons wishing to sponsor a non-EU spouse is one of the key changes that is "tearing British families apart", the cross-party committee found.
Liberal Democrat APPG member Sarah Teather MP said: "We heard from many families in which British children are being made to grow up away from a parent, or where families had been forced to move overseas in order to be together. Whatever the objective of the policy, children shouldn't suffer."
The number of immigrants arriving in Britain has dropped "significantly", according to figures released today.
Net migration has fallen by a third with 163,000 coming to the UK in the year to June 2012, down from 247,000 in the previous year, the Office for National Statistics (ONS) said.
The decline was driven by a drop in the number of immigrants coming to Britain, which fell from 589,000 to 515,000, while the number of migrants leaving the country rose from 342,000 to 352,000.
The estimated total long-term immigration to the UK last year was 566,000, down from 591,000 in 2010. The Office of National Statistics says this is not a statistically significant difference.
A "long-term international migrant" is described as being someone who moves from their country of previous residence for a period of at least a year.
Estimated net migration was 216,000 in the year to December 2011. This is lower, but is not a statistically significant difference, from 252,000 in the year to December 2010, according to the Office for National Statistics.