Mr O’Flynn was a Ukip politician himself, before defecting to the SDP in November last year. He cited the party’s affiliation with far-right activist Tommy Robinson as his reason for leaving. Still firmly behind Brexit, the MEP said the SDP is a centre-left pro-Brexit party.
“And the SDP is a pro-Brexit party will perhaps just to the left of centre views on things like public services and the economy.
“But the prediction I was going to make is that Nigel Farage’s Brexit Party will outpoll Gerard Batten’s Ukip – with its anti-Muslim fundamentalism attached – by about 3-1.”
He added: “The person to teach the establishment a lesson will be Nigel Farage and the Brexit Party.”
Mr O’Flynn, who was previously the Political Editor of the Daily Express, has been an MEP since 2014.
He criticised the new Ukip leadership for its friendliness to the far right.
Nigel Farage himself quit Ukip in December, saying he no longer recognised the party under Gerard Batten.
He said the “fixation” with anti-Muslim policies and appointment of Mr Robinson as an adviser left him dismayed.
Mr Batten has described Islam as a “death cult” and called for controversial policy such as Muslim-only prisons.
Mr Farage has since set up a separate party called the Brexit Party which he claims will spark a political “revolution” and give voters the chance to “fight back against the betrayal of democracy”.
Mr Farage, who tried and failed seven times to become a Ukip MP, has been an MEP since 1999.
He has been the voice of Brexit for many years and plenty of Leavers have flocked to his new party since his departure from Ukip.