Border controls will be placed between Northern Ireland the Republic of Ireland if the UK leaves the EU without a deal, said Jean-Claude Juncker, chief of the European Union's executive arm. Juncker told Britain's Sky News the EU has to "make sure that the interests of the European Union and of the internal market will be preserved."

How to preserve a frictionless border between EU member Ireland and Northern Ireland, which is part of the United Kingdom, is the thorniest issue in the Brexit discussions.

The EU fears a hard border could cause unrest in Northern Ireland and undermine the fragile peace provided by a 1998 peace deal that ended three decades of violence between Irish nationalists seeking a united Ireland, and British security forces and pro-British unionists.

Read more: Brexit: Does Boris Johnson's track record explain the man?

Juncker noted that without a border after a no-deal Brexit, an animal entering Northern Ireland could then enter the EU via Ireland without any controls. "This will not happen," he said. "We have to preserve the health and the safety of our citizens."

Juncker says there is still time for London and Brussels to make a Brexit deal

A deal still possible

The UK is scheduled to leave the EU on October 31. Brexit would be the UK's biggest shift in trade and foreign policy for more than 40 years and deprive the 28-nation bloc of one of its biggest economies. Many warn that a disorderly British departure without an agreement could cause massive economic disruption.

Read more: Boris Johnson saves trickiest Brexit challenge, Northern Ireland, for last

Juncker said there was still time for London and Brussels to make a Brexit deal. He told the Spanish daily El Pais that he had "constructive and partly positive" talks with British Prime Minister Boris Johnson on Monday in Luxembourg.

"I believe that we still have a chance to reach an agreement," the paper quoted Juncker as saying. "I don't share the views of those who think that Johnson is playing games with us and with himself," he said.

The UK's departure from the EU "is a tragic moment for Europe," Juncker stressed.

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sri/sms (AP, Reuters, AFP)

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