Survey results released on Saturday showed that 55 per cent of the British electorate are planning to vote to leave the European Union in the upcoming referendum.
Only 45 per cent of the 2,000 British voters, surveyed by the ORB institute on behalf of the online newspaper The Independent, said they would vote to remain in the EU.
This marks a significant rise in support for a so-called Brexit, or British exit, in Britain's planned in-out referendum on its EU membership on June 23.
In April, 51 per cent said they would vote to leave the EU, with 49 per cent siding with the remain campaign, The Independent said.
The survey results came as a leading Brexit campaigner, Nigel Farage, said that British people would vote to leave the EU and others will follow suit, leading to the "collapse" of the entire project.
"On June 23, Britain will leave the union and will change Europe," the leader of the eurosceptic UK Independence Party (UKIP) said in a Saturday interview with Italian newspaper Corriere della Sera.
"We will have a domino effect. After us, the other northern countries will leave, one after the other. Denmark first, then the Netherlands, Sweden, Austria. This referendum is the most important event since 1957: the EU is about to collapse," he said.
Farage said southern nations like Italy, Greece and Spain would benefit from such a scenario, because the EU's common currency, the euro "is destroying" their economies, while it is also "the weapon for German hegemony."
The UKIP leader said he would have something to celebrate even if voters decided against Brexit. If the Remain camp won, British Prime Minister David Cameron "would still have to resign" because of the divisions on the EU question among his Conservative Party, Farage said.