Sage CEO Stephen Kelly told BI: "I've been disappointed with the complete vacuum of political leadership and I've been disappointed with opportunistic business leaders that use Brexit as an excuse."
Kelly didn't single out any business for specific criticism but several banks such as JPMorgan and HSBC have warned they may have to move thousands of jobs in the wake of the Brexit vote and Vodafone has said it may relocate its headquarters away from Britain.
In a blog post on LinkedIn on Thursday, Kelly attacked "Chicken Little" businesses for scaremongering, writing:
"It was disheartening to see some big multinational businesses announcing post-June 23rd that they will be withdrawing investment or jobs from the
"Of course, I appreciate that every business must plan for the best interests of its customers, colleagues and shareholders. But these announcements - without a clear view of how the coming months and years will pan out - only serve to add to the confusion and anxiety."
Kelly told BI that the Brexit vote had not changed its business day-to-day, saying: "We've modelled different scenarios. Your stakeholders - your community, your shareholders, your suppliers - will be well looked after."
Newcastle-headquartered Sage, which is worth £6.7 billion ($8.8 billion), provides accounting and payroll software for small businesses.
Sage
Kelly is a business ambassador to David Cameron and prior to joining Sage as CEO in 2014 was COO of the coalition government, which took power in 2010.
He told BI: "I was very privileged to have served in the coalition government where I worked with people like Nick Clegg and Danny Alexander. What I saw was the impact of a coalition and how effective it was. It was actually brilliant in driving the manifesto to an effective conclusion."
In another blog post on LinkedIn Kelly singled out talented politicians from across the political spectrum such as London Mayor Sadiq Khan, Labour's shadow business secretary Chuka Umuna, Labour's Gisela Stuart, and Tory leadership contender Andrea Leadsom.
So does that mean Kelly is backing Leadsom to be the next Prime Minister? "I think my responsibility is to small businesses and it's not my role to get involved in their political races," he told BI.
Kelly was speaking to BI during an interview to launch Sage's new survey of millennial entrepreneurs.