The pound has wiped out its gains from earlier in the day, falling in value against the US dollar following the Prime Minister’s speech at the Conservative Party conference.

Sterling dipped by 1.4% to 1.1312 dollars shortly after Liz Truss told the conference that the Government was making “difficult but necessary” choices to stimulate economic growth.

The pound had hit a three-week high against the dollar in early session trading, taking it to around 1.147 dollars.

It followed a short-lived rebound on Tuesday after reports that the Chancellor could be bringing forward the highly anticipated fiscal plan and official economic forecast.

But concerns that the Government has taken on too much debt while ploughing ahead with sweeping tax cuts has continued to spook investors since the unveiling of last week’s mini-budget.

The Chancellor’s fiscal measures are expected to cost around £45 billion, with just £2 billion of that knocked off after the Government’s U-turn on scrapping the 45p tax rate for high earners.

Concerns over how that deficit will be funded has prompted the costs of government borrowing, known as gilt yields, to rise.

Ten-year gilt yields rose by nearly 4% on Wednesday afternoon after Ms Truss’s speech at the party conference.

Last week, the Bank of England stepped in to calm spiralling gilt yields and prevent some pension schemes – which were forced to sell off their gilts – from collapse.

But the temporary gilt-purchasing programme is expected to end in around a week, experts have noted, after which investors will be listening out for an update from the Bank of England as to whether it plans to extend its support.

As Prime Minister Liz Truss took to the stage to try and shore up her support among her party and the country, the pound fell further back and government borrowing costs rose slightly

Susannah Streeter, senior investment and markets analyst at Hargreaves Lansdown, said: “As Prime Minister Liz Truss took to the stage to try and shore up her support among her party and the country, the pound fell further back and government borrowing costs rose slightly.

“She may have hoped that her triple promise of growth would have calmed markets further but with nothing new to offer on the table, her words have not had the desired effect so far.

“The pound dipped below 1.14 dollars, hovering around 1.135 dollars, and 10-year gilt yields lifted a little to a whisker under 4%.

“The speech will do little to quell dissent over worries that public services will bear the brunt of the tax cuts plans.

“Ms Truss will still face an uphill struggle though to convince colleagues and voters that reductions in public spending, which will be necessary to fund tax cuts, won’t end up denting productivity over the longer term instead, especially if working families are made poorer.”