More than half of Brits think immigration has a negative effect on the country, and 47% would deny Bulgarians and Romanians rights to live and work in the UK, a new survey has shown.
A third of people surveyed vastly over-estimated the percentage of people born outside the UK living in the country, thinking the figure was over 40%, rather than the 13% indicated in the 2011 census.
Romanian and Bulgarian ministers have consistently said they do not believe many of their countrymen will seek to come to the UK when restrictions on migrants are relaxed in January, because most who intended to leave have come here already, or gone to other EU nations.
Yet the Sunday Times reported fears about the number of nationals that might come to Britain have led the Prime Minister to consider extending the length of time that new arrivals from the EU have to stay in the country before they gain access to benefits from three months to a year, potentially setting up a clash with Brussels and a row within the coalition Government.
The European Commission prevents member states from discriminating between their own citizens and those from other European Union members.
Ukip won praise for its immigration policies in the survey, with 27% voicing approval, followed by Labour on 18%, the Tories on 12% and Lib Dems on 7%.
Romania's Foreign Minister, Titus Corlatean told Channel 5 News Cameron should reject "in clear terms if it's possible the xenophobic and populistic and once again sometimes racist attitudes which are promoted by some other British politicians".
"Populist rhetoric may win votes today, but the price is paid with the lives and reputation of thousands of hard working Romanians," the Romanian ambassador Dr Ion Jinga told The Huffington Post UK.
In a piece to mark Romania's national day next week, the ambassador said: "I have lived for many years abroad, enough to see that people usually first learn about Romania in what they read in newspapers or see on TV, which is generally limited and recently marked by scaremongering about migration.
"As Ambassador, I had the opportunity to discover Britain's true values: national pride, an incredible rich history, cultural diversity and high moral standards.
"Therefore, it comes as a great surprise to see how attitudes towards Romania have become so easily formed by misguided and biased opinions. I think the British public deserves to understand my country from a different perspective."
The Bulgarian amabassador accused some politicians of making "highly unacceptable ... prejudicial" comments about his countrymen.
Konstantin Dimitrov told the Daily Telegraph that Bulgarians moving to Britain should not be described as "immigrants".
"Bulgarians are not immigrants," he said. "Bulgarians are members of the European Union and are moving freely inside the EU, including the UK."
Although the transitional controls on freedom of movement remain in place until the end of the year, Dimitrov said he had not heard of any Bulgarians being prevented from working in the UK.
He said: "In other words, most of all those who wanted to work here, especially since we became a member of the EU in 2007, have managed to do so."
Occasionally applications for accession worker cards were turned down but this was for technical reasons such as failure to provide the necessary qualifications, he told the newspaper.