Jean-Claude Juncker has threatened to take revenge on Donald Trump for supporting Brexit by launching an independence campaign in the state of Ohio.

The European Commission President said the US President should have stayed out of Britain's referendum.

Mr Trump weighed in to endorse Brexit last summer while the Republican candidate. He was then assisted on his own campaign by the then Ukip leader Nigel Farage.

Since being elected President, Mr Trump has backed voters' decision to quit the EU.

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Jean-Claude Juncker, pictured in Malta today, has threatened to take revenge on Donald Trump for supporting Brexit by launching an independence campaign in the state of Ohio

Mr Trump, pictured at the White House yesterday, weighed in to endorse Brexit last summer while the Republican candidate. He was then assisted on his own campaign by the then Ukip leader Nigel Farage.

Mr Juncker has said he regrets Brexit but vowed to negotiate hard for the remaining 27.

Speaking in Malta today: 'Brexit isn't the end. A lot of people would like it that way - even people on another continent where the newly elected US president was happy that Brexit was taking place and has asked other countries to do the same.

'If he goes on like that, I am going to promote the independence of Ohio and Austin, Texas, in the United States.

'It's business as usual in Europe. We must continue, we must forge ahead.'

Ex Ukip leader Nigel Farage said: 'Juncker has made a complete fool of himself.

'He clearly does not understand the difference between the EU and the United States of America.

'One was formed by consent while the other is being imposed.

'The US is an organically formed nation with a single language and similar culture while the cultural and linguistic differences in the EU are immense.

'If this is what Juncker calls diplomacy, he needs to take a long hard look at himself.'

Europe's leaders have been reacting to Britain's Article 50 notification, which was delivered to Donald Tusk yesterday by Britain's EU ambassador Sir Tim Barrow

Meanwhile, European Parliament president Antonio Tajani told the EU conference in Malta: 'We are living a very difficult moment.

'Economic crisis, immigration, terrorism, Brexit, the responsibility of the EPP (European People's Party) is most important responsibility.

'We need to work all together, we need to be united.'

EU Council President Donald Tusk led reaction from Europe yesterday, insisting Brexit was not a 'happy' day and insisting: 'We already miss you'.

Britain's EU ambassador Sir Tim Barrow set the ball rolling yesterday as handed the Article 50 notification to Mr Tusk at around 12.20pm, formally starting Brexit talks.

Mr Tusk brought his copy to a press statement and showed it off to the cameras.

The letter set out the Prime Minister's objectives for the Brexit negotiations and how she wanted to pursue them.