Angel Gurria, the secretary-general of the OECD (Organization for Economic Co-operation and Development), has accused some leading Brexit campaigners of wanting the UK to leave the EU in order to advance their careers.
Gurria said on Friday there was "absolutely no logic" to the UK leaving the EU at the June 23 referendum.
Speaking to Al Jazeera English's UpFront programme, in an interview conducted before Labour MP Jo Cox was killed, Gurria said Brexit was "bad from every single angle".
"Some [Leave] politicians maybe are trying to profit, advance their careers," he said. “It’s at the expense of the next generation."
The OECD has previously warned the referendum has already hurt growth.
"The leaders of the 'Leave movement' are not appealing to facts or figures," he continued. "They’re appealing to emotions. They are misleading public opinion."
"Already Brexit is happening in the sense that the uncertainty is costing low growth, capital flight, in the last quarter."
Gurria's comments are likely to anger the Vote Leave campaign, which is led by Boris Johnson and Micheal Gove.
Campaigning in the referendum in the UK has been suspended following the murder of Cox.