Growth among British businesses fell to a four-year low in the wake of the Brexit vote and a majority of managers now expect a tough economy in the year ahead, according to a new report.
Only 39% of UK firms surveyed by the Chartered Management Institute said they experienced growth following the June referendum, which was the lowest figure since 2012.
Of the 1,118 UK business managers surveyed, 65% are now pessimistic about the UK's economic prospects over the next 12-18 months, and 49% expect Brexit will have a negative impact on growth over the next three to five years.
Around 35% of bosses polled said they also "lack confidence in current UK leadership and management's ability to capitalise on post-Brexit opportunities".
Three-quarters of those polled said that skill investment would be even more important after the UK left the EU, though 20% said they did not receive the training and development needed to "perform their job effectively" this year.
But only 25% were pessimistic about prospects for their own businesses, in line with levels recorded by the Chartered Management Institute over the past year, while 57% were positive about their business's performance in the year ahead.
Meanwhile, views on whether US president-elect Donald Trump would help or harm business prospects was split.
"Looking to wider external influencers, opinion remains uncertain on what impact the Trump presidency will have on the UK's economic prospects - a situation that reflects the divisive political context and heightened economic uncertainty of 2016," the report said.
About 40% expected an "overtly negative" impact on the UK economy, while 31% expected a positive impact resulting from Mr Trump's leadership.
Ann Francke, CEO at the Chartered Management Institute, said: "In this climate of heightened political uncertainty and economic turbulence, the time is now to position Britain as a global leader in responsible capitalism, targeting essential issues like workplace ethics, inclusivity and executive pay to restore trust and transparency and improve productivity."
She added: "There are uncertain times ahead, but I agree with many of those surveyed that there are opportunities for forward-thinking UK businesses."
Meanwhile, campaign group Leave Means Leave has written to the Chambers of Commerce of the 27 EU member states to push for a "sensible agreement regarding the terms of Britain's exit" and is to launch a tour of European capitals in the New Year to insist that a zero tariff deal is mutually beneficial.
The letter warns that the scale of EU exports to the UK means any trade barriers implemented by the European Commission "will have a detrimental effect on jobs and prosperity in a number of EU states, some where unemployment is already unacceptably high".