Image caption Millions of people will be filling in their census forms over the next week

Nearly two-thirds of people do not regard themselves as "religious", a new survey carried out to coincide with the 2011 Census suggests.

The British Humanist Association (BHA), which commissioned the poll, said people often identified themselves as religious for cultural reasons.

The online poll asked 1,900 adults in England and Wales a question which is on this month's census form.

The Office for National Statistics has defended the wording of the census.

While 61% of the poll's respondents said they did belong to a religion, 65% of those surveyed answered "no" to the further question: "Are you religious?"

Two surveys were commissioned, one covering England and Wales, and the other for Scotland. The Scottish survey was commissioned by the Humanist Society of Scotland.

South of the border, 61% of respondents said they did have a religion.

But only 29% also said they were religious, while 65% said they were not.

This poll is further evidence... that the data produced by the census, used by local and national government as if it indicates religious belief and belonging, is in fact highly misleading Andrew Copson, British Humanist Association

Among respondents who identified themselves as Christian, fewer than half said they believed Jesus Christ was a real person who died, came back to life and was the son of God.

Another 27% said they did not believe that at all, while 25% were unsure.

In Scotland, 42% of respondents said they did not belong to a religion, yet in a further question "Are you religious?" 56% answered "no".

The BHA has complained the wording of the optional census question about religion encourages people to wrongly identify themselves as believers.

In the last census in 2001, 72% of people were classed as Christians - a figure which is much higher than other surveys.

The BHA believes people might tick "yes" to the census question on religion for reasons of cultural identity.

The chief executive of the BHA, Andrew Copson, is running a national campaign encouraging non-religious people to state their unbelief clearly on their census forms.

He said: "This poll is further evidence for a key message of the Census Campaign - that the data produced by the census, used by local and national government as if it indicates religious belief and belonging, is in fact highly misleading.

Religious affiliation

The humanists say data which might indicate a greater amount of religious belief than actually exists, is being used to justify faith schools, and the continuing presence of Anglican bishops in the House of Lords.

The Office for National Statistics has defended the wording of the religion question.

A spokesman told the BBC: "The religion question measures the number of people who self-identify an affiliation with a religion, irrespective of the extent of their religious belief or practice."

The think tank Theos, which undertakes research into religious matters, says attempting to measure cultural affiliation to religion - rather than actual, regular practice - is a good idea, as it shows the broad values society shares.

It also disputes the BHA's assertion that the collected data is used for political purposes.