Chancellor Kwasi Kwarteng will deliver a mini Budget on September 23 after MPs agreed to delay the start of their “party conference recess”.

Kwarteng will commit Liz Truss’s government to a radical programme to boost the UK’s growth rate, including deregulation and tax cuts.

Truss, who will be in the US next week attending the UN General Assembly, agreed to push back the date of the “fiscal event” by a day to accommodate her travel plans.

Kwarteng is expected to unveil cuts to National Insurance and reverse plans to increase corporation tax from 19 per cent to 25 per cent in April.

The chancellor will herald a post-Brexit deregulatory push and wants to scrap the EU bankers’ bonus cap, which was introduced in 2014.