The EU has told the UK to stop “wasting time” and find a solution to the Irish border row, with just two weeks until the next showdown summit over Brexit.

Donald Tusk, the European Council president, turned his fire on Jeremy Hunt for likening the EU to the Soviet Union – accusing ministers of rousing the Tory faithful, instead of striving to reach an agreement.

“Unacceptable remarks that raise the temperature will achieve nothing except wasting more time,” Mr Tusk said.

“I was a party leader myself for 15 years, so I know what the rules of party politics are. But now, once the Tory conference is over, we should get down to business.”

Speaking alongside Leo Varadkar, the Irish president, Mr Tusk made clear the EU remained “united behind Ireland” in its determination to prevent a return to border posts and checks.

But he also made clear his anger at the delay to Theresa May’s promised fresh border proposals – linking it to a reluctance to risk a backlash at the Tory conference.

In Birmingham, Mr Hunt, the foreign secretary, triggered fury across the EU by accusing it of trying to keep the UK in a “prison” with behaviour similar to the Soviet Union.

After the Salzburg summit, the prime minister accused Mr Tusk of showing disrespect, but he tuned that accusation on the UK, saying: “In respecting our partners, we expect the same in return.

“Comparing the European Union to the Soviet Union is as unwise as it is insulting. The Soviet Union was about prisons and gulags, borders and walls, violence against citizens and neighbours.

Brexit threatens life on the Irish border: in pictures Show all 15 1 /15 Brexit threatens life on the Irish border: in pictures Brexit threatens life on the Irish border: in pictures An abandoned shop is seen in Mullan, Co Monaghan. The building was home to four families who left during the Troubles. The town was largely abandoned after the hard border was put in place during the conflict. Mullan has seen some regeneration in recent years, but faces an uncertain future with Brexit on the horizon Reuters Brexit threatens life on the Irish border: in pictures A defaced ‘Welcome to Northern Ireland’ sign stands on the border in Middletown, Co Armagh Reuters Brexit threatens life on the Irish border: in pictures Mervyn Johnson owns a garage in the border town of Pettigo, which straddles the counties of Donegal and Fermanagh. ‘I’ve been here since 1956, it was a bit of a problem for a few years. My premises has been blown up about six or seven times, we just kept building and starting again,’ Johnson said laughing. ‘We just got used to it [the hard border] really but now that it’s gone, we wouldn't like it back again’ Reuters Brexit threatens life on the Irish border: in pictures Farmer Gordon Crockett’s Coshquin farm straddles both Derry/Londonderry in the North and Donegal in the Republic. ‘At the minute there is no real problem, you can cross the border as free as you want. We could cross it six or eight times a day,’ said Crockett. ‘If there was any sort of obstruction it would slow down our work every day’ Reuters Brexit threatens life on the Irish border: in pictures John Murphy flies the European flag outside his home near the border village of Forkhill, Co Armagh Reuters Brexit threatens life on the Irish border: in pictures Potter Brenda McGinn stands outside her Mullan, Co Monaghan, studio – the former Jas Boylan shoe factory which was the main employer in the area until it shut down due to the Troubles. ‘When I came back, this would have been somewhere you would have driven through and have been quite sad. It was a decrepit looking village,’ said McGinn, whose Busy Bee Ceramics is one of a handful of enterprises restoring life to the community. ‘Now this is a revitalised, old hidden village’ Reuters Brexit threatens life on the Irish border: in pictures Union Flag colours painted on kerbstones and bus-stops along the border village of Newbuildings, Co Derry/Londonderry Reuters Brexit threatens life on the Irish border: in pictures Grass reflected in Lattone Lough, which is split by the border between Cavan and Fermanagh, seen from near Ballinacor, Northern Ireland Reuters Brexit threatens life on the Irish border: in pictures Donegalman David McClintock sits in the Border Cafe in the village of Muff, which straddles Donegal and Derry/Londonderry Reuters Brexit threatens life on the Irish border: in pictures An old Irish phone box stands alongside a bus stop in the border town of Glaslough, Co Monaghan Reuters Brexit threatens life on the Irish border: in pictures Billboards are viewed from inside a disused customs hut in Carrickcarnon, Co Down, on the border with Co Louth in the Republic Reuters Brexit threatens life on the Irish border: in pictures Seamus McQuaid takes packages that locals on the Irish side of the border have delivered to his business, McQuaid Auto-Parts, to save money on postal fees, near the Co Fermanagh village of Newtownbutler. ‘I live in the south but the business is in the North,’ said McQaid. "I wholesale into the Republic of Ireland so if there’s duty, I’ll have to set up a company 200 yards up the road to sell to my customers. I’ll have to bring the same product in through Dublin instead of Belfast’ Reuters Brexit threatens life on the Irish border: in pictures A disused Great Northern Railway line and station that was for customs and excise on the border town of Glenfarne, Co Leitrim Reuters Brexit threatens life on the Irish border: in pictures Alice Mullen, from Monaghan in the Republic of Ireland, does her shopping at a former customs post on the border in Middletown, Co Armagh. ‘I’d be very worried if it was a hard border, I remember when people were divided. I would be very afraid of the threat to the peace process, it was a dreadful time to live through. Even to go to mass on a Sunday, you’d have to go through checkpoints. It is terribly stressful,’ said Mullen. ‘All those barricades and boundaries were pulled down. I see it as a huge big exercise of trust and I do believe everyone breathed a sigh of relief’ Reuters Brexit threatens life on the Irish border: in pictures A bus stop and red post box stand in the border town of Jonesborough, Co Armagh Reuters

“The European Union is about freedom and human rights, prosperity and peace, life without fear, it is about democracy and pluralism; a continent without internal borders or walls.

“As the president of the European Council and someone who spent half of my life in the Soviet Bloc, I know what I’m talking about.”

Asked if Mr Hunt should resign over his comments, Mr Tusk replied: “It’s not my problem.”

On the Irish border, he added: “We will not give up seeking a workable solution that fully respects the Good Friday Agreement as well as the integrity of the single market and the customs union.

The EU-imposed deadline for progress is the Brussels summit on October 18, although leaders will hope to agree a deal in outline a few days earlier.

The prime minister is preparing to compromise further, apparently by agreeing to keep the entire UK effectively inside the customs union indefinitely, unless and until technology provides a solution.

This would meet her pledge of no customs border down the Irish Sea, which she has argued would see the EU annex Northern Ireland.

The other change would leave Northern Ireland aligned with single market rules, introducing regulatory checks between Britain and the province.

However, at the Tory conference, Arlene Foster, the Democratic Unionist Party leader, vowed her party would torpedo any such agreement.