Foreign Secretary Jeremy Hunt has urged the EU not to mistake British politeness for weakness after Brexit negotiations reached an impasse.
After rejecting the UK’s proposals, Donald Tusk, head of the European Council, posted a provocative picture on Instagram featuring UK PM Theresa May “cherry-picking” a cake.
Mr Tusk has since said he admires Mrs May, and a compromise is possible.
But Mr Hunt said Mr Tusk needed to avoid “revving up” the situation.
He insisted it was time for people in the EU “to step back from the abyss” of a no-deal Brexit, to “sit down and to talk to us about how we can make these sensible, concrete proposals actually work”.
Mrs May tried to sell her proposals for the UK’s future relationship with the EU at a summit in Salzburg, Austria, this week.
The plan – the so-called Chequers agreement – was agreed by the UK government in July.
But EU leaders rejected a major part of her plan, saying the new economic partnership she had put forward would “not work” and risked “undermining the single market”.
Mrs May later delivered a speech in Downing Street in which she said the EU’s rejection of her plan without offering an alternative was “unacceptable”.
And on Saturday, Mr Hunt said the UK was still waiting for a “detailed response” from the EU and criticised its approach to negotiations so far.
“What Theresa May is saying is ‘don’t mistake British politeness for weakness’,” he told BBC Radio 4’s Today programme.
“If you put us in a difficult corner, we will stand our ground – that is the kind of country we are.
“Insulting her on social media, getting to these stand-offs where you are calling people liars and so on is not the way we are going to get a solution to this difficult situation.”
Mr Hunt refused to rule out the prospect that the government could now seek a Canada-style free trade agreement – as many Conservative MPs want, rather than the more ambitious Chequers plan.
“I am not dismissing anything,” he said.
“We think these proposals are better than the Canada proposals because they work better on the Northern Irish border.”
Canada’s deal with the EU, signed in 2016, removes the vast majority of customs duties on EU exports to Canada and Canadian exports to the EU – but without Canada paying for access to the single market.
The land border between Northern Ireland and EU member the Republic of Ireland has been a stumbling block in negotiations.
Both sides agree they do not want a return to a “hard border”, such as customs posts or a network of surveillance cameras, but the wording is proving hard to agree on.
On Friday, Mr Tusk said Britain had known about the EU’s reservations over the Chequers plan for weeks.
He added that EU leaders at the summit had treated her proposals with “all seriousness” and said he was “convinced that a compromise, good for all, is still possible”.
The UK is due to leave the EU on 29 March 2019 – but the two sides are trying to reach a deal on trade, and other areas of co-operation, by November so it can be ratified in time.