Answering a question posed by Belgium's ambassador to the EU Rudolf Huygelen about some business leaders' post-Brexit concerns, British Foreign Secretary Boris Johnson said "F**k business", according to The Daily Telegraph.
The incident took place during last week's Foreign Office reception to celebrate the Queen's birthday with European diplomats.
In his speech, Jonson also reportedly commented on steps by UK Prime Minister Theresa May to provide a softer Brexit, saying that "we will fight it and we will win."
Admitting that Britain is currently more divided now than it has been since the English Civil War, Jonhson heaped praise on what he touted as a "wonderful project called Brexit."
Speaking to the Daily Telegraph on condition of anonymity, EU diplomats have, meanwhile, expressed dismay about Johnson's use of the expletive, with one of them saying that "it is shocking for him [Johnson] to declare he would take the battle directly to Theresa May and speaking so openly about it."
"I was shocked by how crude and crass he was, as if he didn’t care [about] the consequences and especially not the economic consequences of Brexit," the diplomat said.
Another diplomat noted that "the Conservatives are meant to be the party of business but now it looks like the European Commission is the best friend of British business."
On Saturday, German car giant BMW shared Airbus’s recent concerns over its post-Brexit operations in Britain, threatening to start making "contingency plans" if the company doesn't get details by the end of summer; Germany's BDI industry group and Siemens had taken the same steps earlier on.
The Brexit talks officially kicked off in June 2017 and are expected to be completed by the end of March 2019. Despite a reported breakthrough in the negotiations in March, the sides pointed out a lack of major progress after their talks in April.