The sanctions are now set to run until June 23 2018 and apply to EU citizens and companies

A "visible divide" has opened up within the European Union between the "elite" and the general population, according to a major survey of public opinion across the 28-nation bloc.

The report by the Chatham House international affairs think tank found the "decision makers and influencers" of the EU were notably more optimistic about the future and committed to a common set of European values.

In contrast, it said there was a "simmering discontent" among the wider public over a range of political issues - from immigration to the power of Brussels - with large sections viewing the EU in negative terms.

The report is based on a survey by Kantar Public of more than 10,000 members of the public and 1,800 "influencers" from politics, the media, business and civil society, from 10 EU member states, including the UK.

It found that the "elite" were far likely to feel they had done well out of the EU, with 71% saying they had benefited compared with just 34% of the public.

Members of the elite were twice as likely to say they felt "very proud" of their European identity - 29% compared to 14% of the public.

When it came to the greatest failures of the EU the public were most likely to point to the refugee crisis, bureaucracy and excess regulation, and immigration while the elite emphasised bureaucracy and regulation although they also identified the refugee crisis and immigration.

The survey found the public was more likely to believe another member state would follow Britain and opt to leave the EU - with 55% (not including UK respondents) saying they expected another country to go within the next 10 years compared to 43% of the elite.

Among the British public, 72% said they believed another country would leave - a figure only exceeded by Greece with 80%.

Brexit was not viewed as a significant threat to the EU by the elite who ranked it only 12th out of 15 possible threats to the future of the bloc.

However they were split on the way forward, with 37% of the elite saying the EU should get more powers, 28% supporting the status quo, while 31% thought powers should be returned to member states.

The report said that the survey had exposed a "visible divide" between the general attitudes, beliefs and life experiences of the two groups.

"Compared to the public, decision-makers and influencers are notably more liberal and optimistic, more committed to a pan-European identity and a common set of European values, and more likely to feel the benefits of integration," it said.

"Meanwhile, there is simmering discontent among the public about a range of political concerns.

"Large sections of the public view the EU in negative terms; want to see it return some powers to member states; feel anxious over immigration and its perceived effects, as well as over the role of Islam in society; and are pessimistic about the future.

"Such views are especially strong among those with lower educational qualifications."

Kantar Public surveyed 10,195 members of the public from Austria, Belgium, France, Germany, Greece, Hungary, Italy, Poland, Spain and the UK between December 2016 and January 2017. It interviewed 1,823 politicians, news journalists, business leaders and civil society leaders from the same 10 countries between January 2017 and February 2017.

Online Editors