More than half of British voters would be willing to back a party that promised to "prioritise traditional British values over other cultures", a survey of the levels of support for UK extremist groups has revealed.

Fifty five per cent of those questioned in a poll conducted by YouGov for the Extremis Project, a group tracking the rise in far-right politics, said a party running on this platform would be more likely to win their support.

More than a third of the cross-section of 1,725 people said parties espousing an anti-Islamic stance or pledging to reduce the number of Muslims and the presence of Islam in society would be likely to get their vote.

Two out of five of those questioned said they would support politicians who promised to curb all immigration.

Despite the views expressed, more than half of all respondents indicated that an increase in levels of support for extremism would worry them.

"While underlying cultural tensions still concern large numbers of citizens, we also found that younger generations are far more relaxed about diversity and immigration," said Dr Matthew Goodwin and Anthony Painter, founders of the Extremis Project.

"This provides more evidence that there are sharp generational differences in our attitudes toward these issues, and that mainstream parties that 'talk tough' on these issues risk alienating an emerging, and more tolerant generation of voters."

"The results show that immigration and culture are issues that can cause serious tension in certain conditions," said Dave Rich of the Community Security Trust, adding that these were "precisely the issues that extremist parties try to exploit.

"The survey shows there is still work to be done in reducing intolerance and guarding against extremist parties."