Brussels - EU President Donald Tusk has dismissed plans for post-Brexit relations with London, reportedly devised by the British government, as "based on pure illusion".
Tusk's comments came after Prime Minister Theresa May's cabinet agreed Britain's plans for the future relationship at a marathon meeting. She is due to unveil them in a speech next Friday.
"I'm glad that the UK government seems to be moving towards a more detailed position," said Tusk, who will meet May in London the day before her speech.
"However if the media reports are correct I am afraid that the UK position today is based on pure illusion," the European Council president told a press conference after a summit in Brussels on Friday.
One British minister, who was not present during the cabinet talks in London, said they had agreed that Britain would seek to align itself with European Union rules in certain sectors of the economy, but will retain the right to diverge.
"It looks like the cake philosophy is still alive," Tusk said, referring to earlier comments by British officials that they wanted to "have their cake and eat it" when it came to leaving the EU's single market and enjoying its benefits.
Pros and cons of possible models for a post-Brexit relationship between the UK and the EU
The EU president said there could be "no cherry-picking and no single market a la carte" for Britain, and that the EU would be "absolutely realistic in our proposals."
European Commission President Jean-Claude Juncker then wryly told the assembled reporters: "The president of the council was offering you the headline for tomorrow."
- 'Where is Mr Cameron?' -
Their comments capped a day of digs at the British side in the increasingly tense negotiations over Britain's planned departure from the European Union in March 2019.
Juncker took a swipe at former British prime minister David Cameron, who opposed Juncker's appointment in 2014 but lost his own job two years later after losing the Brexit referendum he had himself called.
"Where is Mr Cameron now?" the former Luxembourg premier said.
"I have heard some rumours that he is in a quiet, comfortable position," quipped Tusk.
Juncker had earlier jokingly suggested that he could do the job better.
"I am not the British prime minister, it would be good for Britain if I was it, but I am not," Juncker told a reporter who quizzed him on when he expected to get details of the outcome of the British cabinet meeting.
May is under pressure to set out more details of her position before talks get underway on the future partnership in April, but with Brussels warning that Britain cannot have everything it wants.
The British Prime Minister gathered around a dozen of her senior Cabinet colleagues for eight hours of talks at her country retreat Chequers on Thursday, in a bid to thrash out their considerable differences.
Tusk said EU leaders would adopt their guidelines for the future relationship at a summit on March 22-23 "whether the UK is ready with its vision or not."
"We cannot stand by and wait," he added.
Irish Prime Minister Leo Varadkar -- whose country wants any Brexit deal to prevent the return of border and customs checks with British-ruled Northern Ireland -- added to the pressure on Britain.
"We'd like to see a very close relationship between the UK and the EU, one that isn't very different from the one we have now, but I don't think the United Kingdom has yet squared the circle," he said.
"Sooner or later that fundamental issue will have to be confronted and I think it would be better done sooner."
By Danny Kemp