The chief secretary to the Treasury has faced online ridicule after celebrating the rise in the pound – just before it repeatedly dropped to a 37-year low.
He tweeted: “Great to see sterling strengthening on the back of the new UK Growth Plan.”
But once the markets digested what amounted to tax cuts costing up to £45 billion annually, the currency went in reverse.
At its lowest point on Friday afternoon £1 could buy just 1.0896 US dollars – the worst exchange rate for Britons since 1985.
It was a drop of over 3%, and means the pound has lost more than 7% of its value against the dollar in just a month.
Twitter was in unforgiving mood.
Appearing on the BBC later, Philp said the markets will see that the government has a “credible and responsible” economic plan
He told BBC Radio 4’s PM programme: “I think when the chancellor sets out his medium-term fiscal plan, which includes getting debt to GDP falling, then I think markets and others will see that we have a credible and responsible plan.”.
He also insisted the government has a “plan” to drive up GDP by 1% on current forecasts every year.
“I have every confidence that the objective we set out, the extra 1%, will be delivered. We’re not hoping, we’ve got a plan to do it.”
Philp rejected the idea that the government has abandoned the cautious approach to the public finances taken by previous Tory administrations.
Using more than £70 billion of increased borrowing, Kwarteng on Friday set out a package which included abolishing the top rate of income tax for the highest earners.
He cut stamp duty for homebuyers, and brought forward a cut to the basic rate of income tax, to 19p in the pound, a year early, to April, as part of tax cuts costing up to £45 billion annually.
Kwarteng told the Commons tax cuts are “central to solving the riddle of growth” as he confirmed plans to axe the cap on bankers’ bonuses while adding restrictions to the welfare system.