Though some Conservative Brexiteers on the British side have publicly advocated a 'no deal', Mr Juncker appeared to allude to people in the shadows on the EU side who also wanted talks to collapse.
The president's intervention comes after details of a dinner between Theresa May and Mr Juncker were leaked to the German press – an action the Commission blamed on people who wanted to undermine negotiations.
"The Commission is not negotiating in a hostile mood. We want the deal. Those who don’t want the deal, the 'no dealers', they have no friends in the Commission," he told the parliament.
"We want a fair deal with Britain and we will have a fair deal with Britain. A no-deal is not our working assumption."
Speaking in the same discussion, however, a key ally of Angela Merkel said it was right to prepare for a 'no deal' scenario.
Manfred Weber, the leader of the European Parliament’s largest political group, the centre-right European People’s Party, said:
“We underlined that there is no sufficient progress, we clarified that there is no cherry picking possible, we are preparing a scenario for leaving without an agreement, I think that is a good step.
“The business community on the London side is getting more and more nervous. The Brexiteers have no common plan for the future of their country and especially their relationships towards the European Union.”
Gianni Pittella, the leader of the socialists group in the Euroepan Parliament, added: “Mr Juncker rightly said we are in favour of an agreement, the deadlock is due to a lack of preparation on behalf of the British government.”
On the British side, Labour said last week it was in talks with sympathetic Tory MPs to stop the Prime Minister from bringing in a 'no deal' Brexit.
More eurosceptic Conservatives have however suggested that a 'no deal' might be the best option, echoing the Prime Minister's slogan that "no deal is better than a bad deal".
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