EU officials on Wednesday expressed irritation at a combative tweet from British Prime Minister Boris Johnson's office claiming Brussels was shifting objectives in upcoming trade talks.
One official, speaking to AFP on condition of anonymity, described the post from the Number 10 press office as "deeply false, dishonest".
The offending tweet republished a two-year-old slide used by EU chief negotiator Michel Barnier displaying the trade options available to the UK according to various negotiating red lines.
Above it, Johnson's press office wrote: "In 2017 the EU showed on their own slide that a Canada-style FTA (free-trade agreement) was the only available relationship for the UK. Now they say it's not on offer after all. Michel Barnier what's changed?"
The tweet referred to the biggest point of contention in the negotiations: the EU's insistence that Britain has to hew to the bloc's labour, environmental and tax standards - to ensure a "level playing field" - if it wants a free-trade pact.
Although that demand has been made in EU documents and in a non-binding political declaration Britain signed last year, the UK is balking at having to abide by EU rules now that it is no longer part of the bloc.
"It's wrong to say we've changed our position. It has always been very clear that a free-trade deal is linked to a level playing field," the EU official said, adding that the UK tweet was received "very negatively" in Brussels.
Another official, also speaking on condition of anonymity, said "this tweet is more meant for the internal debate in the United Kingdom," where several business sectors want to keep close trading ties with the EU.
That official pointed out that each FTA is different, and Britain's situation was unique because it was within Europe with an economy deeply intertwined with its EU neighbours.
"Imports from Canada, Japan and South Korea together are less than UK imports," the official noted.
Britain left the EU at the end of last month but enjoys a transition period to the end of this year, during which it is allowed to trade like an EU member.
That period is meant to provide space to negotiate a deal on a future relationship. But the tone between Brussels and London has been deteriorating, with Britain increasingly saying it is ready to eschew a trade deal rather than cede "sovereignty" to the EU.
The British government's own figures show that the UK economy will suffer from Brexit even if a trade deal would mitigate that to a degree. Without one, potential growth would be crimped further.
Some of the back-and-forth happening now is seen as chest-beating before the negotiations begin next month.