THE pound has been pushed down to its weakest level against the dollar since 2009 amid increasing worries that the UK electorate could vote to exit the European Union.

Sterling tumbled as far as $1.4056 during yesterday's session. By 5pm, it was trading around $1.4157, but this was still down nearly two cents on its pre-weekend close in London of $1.4342.

The pound also lost ground against the euro. The single currency was, at 5pm, trading around 77.87p, up from a pre-weekend close of 77.59p.

Prime Minister David Cameron revealed on Saturday that his promised referendum on the UK’s membership of the European Union would be held on June 23. London Mayor Boris Johnson on Sunday declared his support for “Brexit”, pitting him against Mr Cameron.

Opinion polls have recently signalled the “out” camp has developed a lead as the referendum looms.

Surveys have shown very strong support among business leaders in Scotland to remain in the EU.

And international ratings agencies Moody’s and Fitch yesterday reiterated views that the UK economy could be damaged if the country voted to leave the EU.

Sterling’s tumble came as a survey from the Confederation of British Industry showed the UK manufacturing sector has remained weak this month, with a continuing lack of growth in output volumes.

Of 497 UK manufacturers surveyed, 29 per cent said order books were below normal and only 12 per cent declared they were better than usual. The remainder said order books were normal.

The net 17 per cent reporting below-normal order books signalled a deterioration from the January industrial trends survey, in which a balance of 15 per cent reported weaker-than-usual order books.

Meanwhile, a balance of 19 per cent of UK manufacturers reported that export order books were below normal in the latest survey, which was conducted between January 26 and February 12.

The survey also signalled that UK manufacturers’ output volumes had been flat over the last three months.