Public support for Britain staying in the European Union has risen to a 23-year high, a surprise opinion poll showed today.

Some 56 per cent of people now say they would vote to stay in the EU in a referendum, the highest level since 1991.

Pollsters say the surge in support for remaining in the Euro bloc of 18 countries is in part as a result of the rise of Ukip, with supporters of other parties becoming more determined not to sever ties with Brussels.

Some 56 per cent of people now say they would vote for Britain to stay in the European Union

Support for Nigel Farage's Ukip has soared by 13 points since 2012, but backing for remaining in the EU has risen by 12 points, as David Cameron prepares to renegotiate Britain's membership

The new IpsosMORI survey shows how Ukip's growing popularity has coincided with increasing support for Britain's membership of the EU.

In November 2012, Ukip was on just 3 per cent in opinion polls and 48 per cent backed leaving the EU, with only 44 per cent in favour of staying in.

However, with Ukip now on 16 per cent, Nigel Farage's dream of exit from the EU appears to be further away.

While Ukip has risen 13 points in the polls, the number wishing to leave the EU has fallen by 12 points, IpsosMORI found.

Gideon Skinner, head of political research at Ipsos MORI, said: 'With the debate about Britain's relationship with the EU a hot topic right now, our poll shows support for Britain's membership is up significantly since the depths of the Eurozone debt crisis in 2011 – although that does not mean that the public simply want the relationship to stay the same.

'There is a polarisation in views - Ukip supporters are twice as likely to say Europe is going to be important to their vote in the next election (although it is still some way behind immigration) and are much more sceptical, while supporters of the other parties put the issue lower down on their list and are more in favour of membership.'

The poll reveals the highest level of support for remaining in the EU since 1991, coinciding with the rise of Ukip

Among Labour, Tory and Lib Dem voters, a majority are in favour of remaining in the EU.

More than half (51 per cent) of Conservatives, 73 per cent of Labour voters and 82 per cent of Lib Dems want Britain to stay in. But contrast, just 11 per cent of Ukip supporters want to stay in.

Support for staying in the EU is highest in London (66 per cent) and Scotland (60 per cent).

Angry Eurosceptic Conservative MPs blamed Nigel Farage, saying Ukip has increasingly ‘toxified’ the case for a British exit beyond its core support.

Tory MP Michael Fabricant, a former vice-chairman of the party, said: ‘Today’s poll puts into stark reality what would be the outcome if there were a referendum on the EU in the next 12 months, which is being demanded by Ukip.

It is ironic that it is Ukip and some other Eurosceptics who... are setting back the out argument Tory MP Michael Fabricant

‘It is ironic indeed that it is Ukip and some other Eurosceptics who, through their relentless negativity and messages without any hope, are setting back the out argument.'

Tory MP Stewart Jackson added: ‘The challenge is to make a positive case for the UK as a global trading nation whereas the EU is shrinking as a world market.’

However, pro-Europeans welcomed the news that support for staying in the EU has risen.

Lib Dem President Tim Farron said: ‘It's an encouraging sign that vindicates the courage shown by the Lib Dems being the lone voice in favour of the UK being better off working together with our neighbours in Europe.’

A Ukip spokesman, meanwhile, said 51 per cent agreed with the party's call for a 'free trade deal with the EU, against 43 per cent who want to keep the status quo or deepen ties'.

The spokesman said: 'We can live with those statistics. Of course when Cameron dangles impossible negotiations under people's noses then people want to believe him, but when he fails - as he surely will - then the polls will harden.'

Alisdair McIntosh, Director of Business for New Europe, said: 'Many of the public recognise the important economic benefits of staying within the EU.

'Politicians are mistaken if they think people just want to hear ever-louder eurosceptic rhetoric, especially at a time of economic and political uncertainty. This only increases cynicism about the major political parties.'

David Cameron has promised to renegotiate Britain's membership of the EU, before holding an in-out referendum by 2017.

Jean-Claude Juncker, who was voted in as the new European Commission president in Strasbourg today, has called to make freedom of movement easier

The Prime Minister vowed to put tackling immigration 'at the heart' of his efforts to reform Brussels' grip on the UK.

He is set to outline plans to limit the number of European migrants joining the workforce within the next few weeks.

However, Mr Cameron suffered a fresh set back today after new Brussels chief Jean-Claude Juncker said freedom of movement should be made easier.

Mr Juncker, who became European Commission president despite the fierce objections of Mr Cameron, told one of his new commissioners to 'promote freedom of movement' within the EU.

Outgoing European Commission chief Jose Manuel Barroso insisted over the weekend that an arbitrary cap on EU immigration would be incompatible with EU law.

Mr Juncker's call for EU migration to be made even easier is a further blow to the Prime Minister.