Jean-Claude Juncker has warned there will have to be controls at the border in Ireland in the event of a no-deal Brexit.

In an outspoken interview, the European Commission president said the UK would be to blame for any fallout for a chaotic exit for the bloc – as the EU “did not invent the Brexit”.

Mr Juncker said he wanted to reach an agreement with the UK but the EU had to protect the safety of its citizens.

The Irish border issue has been a major stumbling block in the Brexit negotiations, as Boris Johnson has demanded that the backstop – a contingency plan to prevent a hard border by keeping the UK aligned with many of Brussels’ rules – should be scrapped.

He told Sky News’s Ridge on Sunday: “We have to make sure that the interests of the European Union and of the internal market will be preserved.

“An animal entering Northern Ireland without border control can enter without any kind of control the European Union via the southern part of the Irish island.

Thousands protest after Boris Johnson requests to suspend parliament Show all 29 1 /29 Thousands protest after Boris Johnson requests to suspend parliament Thousands protest after Boris Johnson requests to suspend parliament Houses of Parliament An anti-Brexit supporter raises a sign during a protest in front of the Houses of Parliament in central London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson maneuvered on Wednesday to give his political opponents even less time to block a no-deal Brexit before the Oct. 31 withdrawal deadline, winning Queen Elizabeth II's approval to suspend Parliament. (AP Photo/Vudi Xhymshiti) Vudi Xhymshiti AP Thousands protest after Boris Johnson requests to suspend parliament Downing Street Anti-Brexit demonstrators hold placards as they protest outside of Downing Street in London on August 28, 2019. - British Prime Minister Boris Johnson sparked fury Wednesday among pro-Europeans and MPs opposed to a no-deal Brexit by forcing the suspension of parliament weeks before Britain's EU departure date. The pound slid on the surprise news, which opponents branded a "coup" and a "declaration of war" but Johnson claimed was necessary to allow him to pursue a "bold and ambitious" new domestic legislative agenda. (Photo by DANIEL SORABJI / AFP)DANIEL SORABJI/AFP/Getty Images DANIEL SORABJI AFP/Getty Images Thousands protest after Boris Johnson requests to suspend parliament Houses of Parliament Anti-Brexit supporters take part in a protest in front of the Houses of Parliament in central London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson maneuvered on Wednesday to give his political opponents even less time to block a no-deal Brexit before the Oct. 31 withdrawal deadline, winning Queen Elizabeth II's approval to suspend Parliament. (AP Photo/Vudi Xhymshiti) Vudi Xhymshiti AP Thousands protest after Boris Johnson requests to suspend parliament Houses of Parliament to Downing Street TOPSHOT - Anti-Brexit demonstrators hold placards as they take part in a protest march from Britain's Houses of Parliament to Downing Street in London on August 28, 2019. - British Prime Minister Boris Johnson announced Wednesday that the suspension of parliament would be extended until October 14 -- just two weeks before the UK is set to leave the EU -- enraging anti-Brexit MPs. MPs will return to London later than in recent years, giving pro-EU lawmakers less time than expected to thwart Johnson's Brexit plans before Britain is due to leave the European Union on October 31. (Photo by DANIEL SORABJI / AFP)DANIEL SORABJI/AFP/Getty Images DANIEL SORABJI AFP/Getty Images Thousands protest after Boris Johnson requests to suspend parliament Downing Street Anti-Brexit supporters gather outside the Prime Minister's residence 10 Downing Street in London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson asked Queen Elizabeth II on Wednesday to suspend Parliament, throwing down the gauntlet to his critics and causing outrage among opposition leaders who will have even less time to thwart a no-deal Brexit. (AP Photo/Matt Dunham) Matt Dunham AP Thousands protest after Boris Johnson requests to suspend parliament Houses of Parliament LONDON, ENGLAND - AUGUST 28: Pro-EU supporters protest outside the Houses of Parliament on August 28, 2019 in London, England. British Prime Minister Boris Johnson has written to Cabinet colleagues telling them that his government has requested the Queen suspend parliament for longer than the usual conference season. Parliament will return for a new session with a Queen's Speech on 14 October 2019. Some Remain supporting MPs believe this move to be a ploy to hinder legislation preventing a No Deal Brexit. (Photo by Peter Summers/Getty Images) Peter Summers Getty Images Thousands protest after Boris Johnson requests to suspend parliament Houses of Parliament epa07799808 A protestor outside the Houses of Parliament in Westminster, London, Britain, 28 August 2019. The UK government is to suspend Parliament after the summer break, a move that might block MPs from voting against a possible no-deal Brexit.. EPA/WILL OLIVER WILL OLIVER EPA Thousands protest after Boris Johnson requests to suspend parliament Houses of Parliament Anti-Brexit supporters take part in a protest near the Houses of Parliament in central London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson asked Queen Elizabeth II on Wednesday to suspend Parliament, throwing down the gauntlet to his critics and causing outrage among opposition leaders who will have even less time to thwart a no-deal Brexit. (AP Photo/Matt Dunham) Matt Dunham AP Thousands protest after Boris Johnson requests to suspend parliament Whitehall TOPSHOT - Demonstrators hold placards as they protest on Whitehall, near the entrance to Downing Street in London on August 28, 2019. - British Prime Minister Boris Johnson sparked fury Wednesday among pro-Europeans and MPs opposed to a no-deal Brexit by forcing the suspension of parliament weeks before Britain's EU departure date. The pound slid on the surprise news, which opponents branded a "coup" and a "declaration of war" but Johnson claimed was necessary to allow him to pursue a "bold and ambitious" new domestic legislative agenda. (Photo by DANIEL SORABJI / AFP)DANIEL SORABJI/AFP/Getty Images DANIEL SORABJI AFP/Getty Images Thousands protest after Boris Johnson requests to suspend parliament Houses of Parliament Anti-Brexit supporters take part in a protest at College Green near the Houses of Parliament in central London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson maneuvered Wednesday to give his political opponents even less time to block a no-deal Brexit before the Oct. 31 withdrawal deadline, winning Queen Elizabeth II's approval to suspend Parliament. (AP Photo/Matt Dunham) Matt Dunham AP Thousands protest after Boris Johnson requests to suspend parliament Anti-Brexit supporters take part in a protest at College Green near the Houses of Parliament in central London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson maneuvered Wednesday to give his political opponents even less time to block a no-deal Brexit before the Oct. 31 withdrawal deadline, winning Queen Elizabeth II's approval to suspend Parliament. (AP Photo/Matt Dunham) Matt Dunham AP Thousands protest after Boris Johnson requests to suspend parliament Protestors from the European Movement in Scotland hold a walking vigil on the Royal Mile, Edinburgh, to demonstrate against Prime Minister Boris Johnson temporarily closing down the Commons from the second week of September until October 14 when there will be a Queen's Speech to open a new session of Parliament. PRESS ASSOCIATION Photo. Picture date: Wednesday August 28, 2019. See PA story POLITICS Brexit. Photo credit should read: Jane Barlow/PA Wire Jane Barlow PA Thousands protest after Boris Johnson requests to suspend parliament Anti-Brexit supporters shout slogans as they gather outside the Prime Minister's residence 10 Downing Street in London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson asked Queen Elizabeth II on Wednesday to suspend Parliament, throwing down the gauntlet to his critics and causing outrage among opposition leaders who will have even less time to thwart a no-deal Brexit. (AP Photo/Matt Dunham) Matt Dunham AP Thousands protest after Boris Johnson requests to suspend parliament Anti-Brexit supporters take part in a protest at College Green near the Houses of Parliament in central London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson maneuvered Wednesday to give his political opponents even less time to block a no-deal Brexit before the Oct. 31 withdrawal deadline, winning Queen Elizabeth II's approval to suspend Parliament. (AP Photo/Matt Dunham) Matt Dunham AP Thousands protest after Boris Johnson requests to suspend parliament Anti-Brexit supporters take part in a protest at College Green near the Houses of Parliament in central London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson maneuvered Wednesday to give his political opponents even less time to block a no-deal Brexit before the Oct. 31 withdrawal deadline, winning Queen Elizabeth II's approval to suspend Parliament. (AP Photo/Matt Dunham) Matt Dunham AP Thousands protest after Boris Johnson requests to suspend parliament Anti-Brexit supporters gather outside the Prime Minister's residence 10 Downing Street in London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson asked Queen Elizabeth II on Wednesday to suspend Parliament, throwing down the gauntlet to his critics and causing outrage among opposition leaders who will have even less time to thwart a no-deal Brexit. (AP Photo/Matt Dunham) Matt Dunham AP Thousands protest after Boris Johnson requests to suspend parliament Anti-Brexit supporters take part in a protest at College Green near the Houses of Parliament in central London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson maneuvered Wednesday to give his political opponents even less time to block a no-deal Brexit before the Oct. 31 withdrawal deadline, winning Queen Elizabeth II's approval to suspend Parliament. (AP Photo/Matt Dunham) Matt Dunham AP Thousands protest after Boris Johnson requests to suspend parliament Shadow home secretary Diane Abbott addresses protesters outside the Houses of Parliament, London, to demonstrate against Prime Minister Boris Johnson temporarily closing down the Commons from the second week of September until October 14 when there will be a Queen's Speech to open a new session of Parliament. PRESS ASSOCIATION Photo. Picture date: Wednesday August 28, 2019. See PA story POLITICS Brexit. Photo credit should read: Kirsty O'Connor/PA Wire Kirsty O'Connor PA Thousands protest after Boris Johnson requests to suspend parliament epa07799846 Protesters gather outside the Houses of Parliament in Westminster, London, Britain, 28 August 2019. The UK government is to suspend Parliament after the summer break, a move that might block MPs from voting against a possible no-deal Brexit. EPA/WILL OLIVER WILL OLIVER EPA Thousands protest after Boris Johnson requests to suspend parliament Anti-Brexit supporters gather outside the Prime Minister's residence 10 Downing Street in London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson asked Queen Elizabeth II on Wednesday to suspend Parliament, throwing down the gauntlet to his critics and causing outrage among opposition leaders who will have even less time to thwart a no-deal Brexit. (AP Photo/Matt Dunham) Matt Dunham AP Thousands protest after Boris Johnson requests to suspend parliament Anti-Brexit supporters carry a flare near the Cenotaph in central London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson asked Queen Elizabeth II on Wednesday to suspend Parliament, throwing down the gauntlet to his critics and causing outrage among opposition leaders who will have even less time to thwart a no-deal Brexit. (AP Photo/Matt Dunham) Matt Dunham AP Thousands protest after Boris Johnson requests to suspend parliament Anti-Brexit demonstrators hold placards as they protest outside of Downing Street in London on August 28, 2019. - British Prime Minister Boris Johnson sparked fury Wednesday among pro-Europeans and MPs opposed to a no-deal Brexit by forcing the suspension of parliament weeks before Britain's EU departure date. The pound slid on the surprise news, which opponents branded a "coup" and a "declaration of war" but Johnson claimed was necessary to allow him to pursue a "bold and ambitious" new domestic legislative agenda. (Photo by DANIEL SORABJI / AFP)DANIEL SORABJI/AFP/Getty Images DANIEL SORABJI AFP/Getty Images Thousands protest after Boris Johnson requests to suspend parliament Anti-Brexit demonstrators hold placards as they protest outside of Downing Street in London on August 28, 2019. - British Prime Minister Boris Johnson sparked fury Wednesday among pro-Europeans and MPs opposed to a no-deal Brexit by forcing the suspension of parliament weeks before Britain's EU departure date. The pound slid on the surprise news, which opponents branded a "coup" and a "declaration of war" but Johnson claimed was necessary to allow him to pursue a "bold and ambitious" new domestic legislative agenda. (Photo by DANIEL SORABJI / AFP)DANIEL SORABJI/AFP/Getty Images DANIEL SORABJI AFP/Getty Images Thousands protest after Boris Johnson requests to suspend parliament LONDON, ENGLAND - AUGUST 28: Pro-EU supporters protest outside the Houses of Parliament on August 28, 2019 in London, England. British Prime Minister Boris Johnson has written to Cabinet colleagues telling them that his government has requested the Queen suspend parliament for longer than the usual conference season. Parliament will return for a new session with a Queen's Speech on 14 October 2019. Some Remain supporting MPs believe this move to be a ploy to hinder legislation preventing a No Deal Brexit. (Photo by Peter Summers/Getty Images)(Photo by Peter Summers/Getty Images) Peter Summers Getty Images Thousands protest after Boris Johnson requests to suspend parliament Anti-Brexit supporters continue to participate in a late evening protest in front of the Houses of Parliament in central London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson maneuvered on Wednesday to give his political opponents even less time to block a no-deal Brexit before the Oct. 31 withdrawal deadline, winning Queen Elizabeth II's approval to suspend Parliament. (AP Photo/Vudi Xhymshiti) Vudi Xhymshiti AP Thousands protest after Boris Johnson requests to suspend parliament London metropolitan police talk with anti-Brexit supporters in front of the Houses of Parliament in central London, Wednesday, Aug. 28, 2019. British Prime Minister Boris Johnson maneuvered on Wednesday to give his political opponents even less time to block a no-deal Brexit before the Oct. 31 withdrawal deadline, winning Queen Elizabeth II's approval to suspend Parliament. (AP Photo/Vudi Xhymshiti) Vudi Xhymshiti AP Thousands protest after Boris Johnson requests to suspend parliament LONDON, ENGLAND - AUGUST 28: A Pro-EU supporter raises her fist during a protest outside the Houses of Parliament on August 28, 2019 in London, England. British Prime Minister Boris Johnson has written to Cabinet colleagues telling them that his government has requested the Queen suspend parliament for longer than the usual conference season. Parliament will return for a new session with a Queen's Speech on 14 October 2019. Some Remain supporting MPs believe this move to be a ploy to hinder legislation preventing a No Deal Brexit. (Photo by Peter Summers/Getty Images) Peter Summers Getty Images Thousands protest after Boris Johnson requests to suspend parliament LONDON, ENGLAND - AUGUST 28: Pro-EU supporters protest outside the Houses of Parliament on August 28, 2019 in London, England. British Prime Minister Boris Johnson has written to Cabinet colleagues telling them that his government has requested the Queen suspend parliament for longer than the usual conference season. Parliament will return for a new session with a Queen's Speech on 14 October 2019. Some Remain supporting MPs believe this move to be a ploy to hinder legislation preventing a No Deal Brexit. (Photo by Peter Summers/Getty Images)(Photo by Peter Summers/Getty Images) Peter Summers Getty Images Thousands protest after Boris Johnson requests to suspend parliament LONDON, ENGLAND - AUGUST 28: Pro-EU supporters protest outside the Houses of Parliament on August 28, 2019 in London, England. British Prime Minister Boris Johnson has written to Cabinet colleagues telling them that his government has requested the Queen suspend parliament for longer than the usual conference season. Parliament will return for a new session with a Queen's Speech on 14 October 2019. Some Remain supporting MPs believe this move to be a ploy to hinder legislation preventing a No Deal Brexit. (Photo by Peter Summers/Getty Images)(Photo by Peter Summers/Getty Images) Peter Summers Getty Images

“This will not happen. We have to preserve the health and the safety of our citizens.”

Meanwhile, foreign secretary Dominic Raab rejected any suggestion that Northern Ireland could have different customs and regulatory arrangements from the rest of the UK, telling BBC1’s Andrew Marr Show: “As a general overarching [arrangement] across all of the rules, no, of course that would be wrong.”

He added: “There couldn’t be a Northern Ireland-only backstop in its entirety in the way it was proposed previously. But on agri-food, and the question of the way the island of Ireland is already managed, that is something in a very discrete area where we can continue talking. But it must have the consent of the parties in Northern Ireland.”

Mr Raab said he was “confident there’s a deal to be done” and insisted the UK was making “good progress” in talks.

“I think what’s necessary now is for the EU to match some of the words that we heard from Jean-Claude Juncker with the detailed negotiations to remove the undemocratic backstop, to be clear we can transition to a best-in-class free trade agreement,” he said. “I think that would be good for the UK but also for the EU.”

Mr Juncker accused some unnamed MPs of “forgetting about the history” of the border in Ireland and fired off a warning that a no deal could see a return to the violence of the past.

The commission president said: “I don’t like a border because after the Good Friday Agreement, and this Good Friday Agreement has to be respected in all its parts, the situation in Ireland has improved.

“We should not play with this ... Sometimes I have to question that some people are forgetting about the history.”

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The senior Brussels official also sought to blame the UK for any fallout caused by a no-deal Brexit, amid frustration in EU circles over perceived attempts from the UK government to shift responsibility away from London.

He said: “The EU is in no way responsible for any kind of consequences entailed by the Brexit.

“That’s a British decision, a sovereign decision that we are respecting but don’t try... not you but to charge the European Union with the responsibility.

“The European Union is not leaving the United Kingdom, the United Kingdom is leaving the European Union.”

Asked who is responsible, he said: “The United Kingdom. Because we did not invent the Brexit.

“We were never pleading in favour of any kind of Brexit. That’s a British decision and so it has to be dealt with in that way.”

His comments came after a meeting with Mr Johnson in Luxembourg last week, when the country’s prime minister Xavier Bettel left an empty podium for his UK counterpart at a press conference.