In the same interview, the European Commission president deflected rumours in the British media of his alleged drinking problem, following several incidents where he appeared unsteady on his feet in public.
“I still have sciatica. This is why I have some mobility problems, which the British press often likes to make a big thing about and attribute to other causes.,” he said.
“I often limp because I had a car accident. But I am not complaining.”
Mr Juncker, in what may prove to be his last newspaper interview as EU Commission chief, made the appeal to British MPs as the UK prepares to elect members of the European parliament, a legal condition of the six-month Article 50 extension.
Brussels fears those elections could lead to a surge in support for far-Right populist parties, such as the Italian Northern League, which are sympathetic towards the causes of Brexit.
In the UK, the vote is also likely to elect swathes of pro-Brexit MPs led by Nigel Farage, whose new Brexit Party could secure nearly a third of the vote according to recent polls.
Mr Juncker went on to say that the EU should stop campaigning for a “United States of Europe.”
Asked if the EU would ever become a United States of Europe, he responded: “I last used this term before puberty at the age of 14 years. We should stop using it. I do not believe that we will ever have a centralised state that is comparable to the U.S. I don’t want it either.