SNP ministers were under fire last night after claims that the 2011 census form north of the Border will not allow Scots to say that they are both Scottish and British.

Tory and Labour MSPs at Holyrood were furious after it emerged that the draft census questionnaire in Scotland will split up British and Scottish as potential ethnicity options. In the draft questions for “ethnic group”, people answering section A will be forced to tick just one box, which separates the Scottish and British options.

Murdo Fraser, the Scottish Conservative deputy leader, said: “Incredibly, the census does not do the same for Chinese-Scottish, Pakistani-Scottish, Indian-Scottish, Bangladeshi-Scottish and other options too.

“Whilst these are valid options as well, it is a disgrace that British-Scottish is not included.”

Mr Fraser added that many people in Scotland were comfortable describing themselves as “Scottish and British” and would be disturbed that the proposed census form would not allow them to identify themselves in that way.

“It may well suit the SNP's narrow agenda to set up the census form along these lines, but it does not reflect the reality of life in Scotland today where millions of citizens are entirely comfortable with the concept of dual identity from all over the world. That should include ‘Scottish and British' as an option”, Mr Fraser said.

Michael McMahon, Labour business manager, said the question options were “crass”. He added: “You can't put people into boxes in this way. Many Scots consider themselves to be both British and Scottish but his survey makes you choose.

“It is completely wrong to force people to choose between their ethnic identities in this way. The fact that people of a non-white background can choose multiple identities, but white people have to choose makes it even more ludicrous.

“What this census hopes to achieve from asking this question is beyond any rational comprehension.”

A spokesman for the Scottish government pointed out that in the national identity part of the census form, Scots would be able to describe themselves Scottish and British. He added: “In the ethnicity section, there is a space at the bottom of the list where respondents can say they regard themselves as Scottish and British.”

Mr Fraser also complained that another question in the draft Scottish form asked for the total income of each household. He said that he hoped this would not be a compulsory question, although there was no indication of that.

“Far better that it is not asked at all”, said Mr Fraser. “It is vital that Scots retain their rights to privacy in these matters.”

The government spokesman said that “although people who did not fill in a census form could be fined up to £1,000, it was extremely unlikely they would face a penalty” because they did not want to fill in the answer to one question.

“In any case”, he added, “the census is anonymous and information is kept secure for years. Registrars would be more than happy to discuss these concerns with anyone.”

The nationwide census, costing almost £500 million, will be an attempt to measure Britain's true immigrant population. New questions have been added to try to establish how long people have been living here, what passports they hold and what their nationality is.

Ministers have been forced to admit they have no idea how many immigrants are in Britain, which means public services in areas of high migrant populations are often stretched to breaking point because spending decisions are based on inaccurate data.

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