The 2011 Census will contain a civil partnerships section but questions on sexual orientation have been omitted, the Office of National Statistics (ONS) has revealed.

However, a nationwide government survey which includes questions on sexuality will be sent to UK households as part of a bid to calculate the amount lesbian, gay, and bisexual people living in Britain.

The ONS defended the exclusion of sexual orientation from the Census, claiming it didn’t feel it was ready to cover such an issue after the reaction in previous years to queries on ethnicity in 1991 and religion in 2001.

A spokesman highlighted issues of definition and acceptability. Census coordinator, Joy Dobbs told the Times, “In the statistical world we are at a very early stage with this and we are still not sure what it is we are trying to measure -is it behaviour, inclination, identity, lifestyle?”

Officials have aimed to appease gay groups by including the question in an existing surveys, possibly the General Household Survey of 20,000 households.

Alan Wardle, of gay group Stonewall, told the Guardian, “We need to ask this question to help tackle equality and discrimination issues, but also because it has implications for service provision.”

The gay community is currently estimated at 6% of all adults. More accurate statistics will make it easier for the new Commission for Equality and Human Rights to guarantee protection and support for people’s sexual orientation.

A new question added to the 2011 Census will ask if people identify themselves as British, Scottish, Welsh or Irish.