National identity will have an influence on how people vote in next month's European elections, according to new research which found the appeal of the UK Independence Party (Ukip) is much stronger in England than it is in Scotland or Wales.
The research suggested that in England, Ukip is challenging Labour for first place in the European Parliament elections on May 22.
A survey found 29% of people in England intend voting for Nigel Farage's party, just behind the 30% set to back Labour. A total of 22% said they would vote for the Conservatives, while 11% said they would be voting Liberal Democrat.
But in Scotland, only one in 10 of those surveyed said they would be voting Ukip, compared with the 33% who plan to vote SNP and the 31% who said they would back Labour. Scottish support for the Tories in the European elections was put at 12%, while for the Liberal Democrats it was 7%.
In Wales, support for Labour was almost twice the level of support for Ukip, with the survey suggesting 39% of voters would back Ed Miliband's party compared with the 20% who said they would vote Ukip. A total of 18% of Welsh voters who were surveyed plan to vote Tory, with 11% backing Plaid Cymru and 7% supporting the Liberal Democrats.
Within England, Ukip support was found to be stronger among those who identified themselves as being English rather than British.
More than two fifths (42%) of those who described themselves as being "English only" or "more English than British" plan on voting Ukip, compared with 19% of those who said they were "British only" or "more British than English".
Support for staying in the European Union was highest in Scotland, with 48% of those surveyed north of the border saying they would vote to remain in the EU if there was an in/out referendum, compared with 39% in Wales and 37% in England.
England was most Eurosceptic, with 40% of people saying they would vote to leave the EU if a referendum was held, compared with 35% in Wales and 32% in Scotland.
The research was carried out by the Scottish Centre on Constitutional Change at Edinburgh University, together with Cardiff University and the Institute for Public Policy Research (IPPR) think-tank.
A total of 3,695 people in England were questioned for the research - which was funded by the Economic and Social Research Council (ESRC) - as well as 1,014 in Scotland and 1,027 people in Wales.
Professor Richard Wyn Jones, director of the Wales Governance Centre at Cardiff University and co-author of the study, said: "Although Ukip's name - the UK Independence Party - suggests it is aimed at those with a British identity, our research shows that it is the party of choice for those who identify as being more English than British."
He added: "There is now a significant chance that Ukip will top the European election poll in England. However, while Ukip are also currently on course to win an MEP in Wales, if the results of this research were repeated on 22 May, they would likely not win an MEP in Scotland. Such a result would highlight the political differences between the nations of Britain."
Another of the report's authors, Professor Ailsa Henderson, the head of politics and international relations at the University of Edinburgh, said: "We now have clear evidence that national identity plays a key role in voters' views about Europe. It will affect the choices people will make in the May 22 elections and, in England, the way people would vote in any referendum on EU membership. These effects vary across Britain, with 'Scottish' and 'Welsh' identifiers backing entirely different parties from 'English' identifiers."
Glenn Gottfried, of the IPPR, said: "Attitudes to Europe vary significantly across the nations of the UK. The English are the most Eurosceptic while the Scots are the most positive about Britain's membership.
"These differences in outlook between England and Scotland could have an impact on the Scottish independence referendum. A strong performance by Ukip in May's European elections might encourage Scots into the Yes camp if they read it as a signal that England may vote to leave the EU in a future in-out referendum on Europe."
SNP European candidate Tasmina Ahmed-Sheikh said the research was " the latest demonstration that people in Scotland are simply not buying the anti-EU obsession of the Westminster parties".
She added: " While Ukip may be calling the shots south of the border, their jobs-destroying agenda is getting them nowhere in Scotland."
Blair Jenkins, the chief executive of the pro-independence yes Scotland campaign, said: " This research shows there is now a real chance that Ukip will top the European election poll in England, whereas here in Scotland Ukip is likely to be comprehensively rejected."