London: Brexit backers moved into a lead in the polls on Monday for the first time in weeks, putting pressure on the pound and raising pressure on Prime Minister David Cameron ahead of Britain's EU referendum.
The WhatUKThinks average now puts "Leave" at 51 percent against "Remain" at 49 percent ahead of the 23 June vote that could see financial markets plunge and hit global economic growth if Britain votes to go.
The balance tipped in favour of "Leave" after two polls at the weekend and one on Monday put them ahead. The last time it put "Leave" in the lead was on 12 May.
The vote could see Britain become the first country to leave the European Union and is being closely watched in countries where Euroscepticism is growing.
The "Remain" camp led by Cameron has warned of the economic dangers of leaving, while "Leave" supporters such as former London mayor Boris Johnson have said they want to curb immigrants from other parts of Europe.
Cameron took part in an event with political opponents Labour, the Liberal Democrats and Greens to accuse "Leave" supporters of "perpetuating an economic con-trick on the British people".
"While they peddle fantasy politics, in the real world our economy is slowing because of the huge uncertainty hanging over Britain's economic future," Cameron said at the "Britain Stronger In" event.
The broadside came after Johnson, who is seen as the most likely successor to Cameron, warned Britain would have to pay more for membership of the EU. "The risks of 'Remain' are massive," he said.
Conservative former prime minister John Major on Sunday accused Johnson, a charismatic politician with popular appeal, of being a "python" who could not be trusted, in a scathing personal attack.
Financial markets have proved volatile ahead of the vote and have been particularly so as the campaign has heated up.
The pound fell to 79.05 pence against the euro in Asian trading-its lowest level in three and a half weeks-and stood at around 78.61 pence against the euro at around 0910 GMT.
The pound also fell against the dollar to $1.4353-a three-week low point.