The newly-elected Ukip leader, Richard Braine, has claimed Brexit is being betrayed by “a traitor class” in the establishment and the media, which he sees as conspiring with the EU.

In a lengthy and at times free-wheeling inaugural press conference in London, Braine lambasted what he portrayed as the “EU cult” and reiterated his views about what he saw as an expansionist, violent culture within Islam.

But his strongest language was reserved for the media. He opened the event by saying he had been abused and shouted at the previous evening by a journalist “full of loathing”.

“My abuser is an example of a new extremism which is being fuelled by a powerful establishment in this country,” Braine said. “Our establishment does the EU’s bidding, and want to turn around the result of Ukip’s glorious referendum.

“I ask you, the media, to cease and desist from stirring this up. Stop calling people uneducated, hateful bigots, racists, scum. Stop calling people far-right when they’re not far-right.”

Asked who was controlling this media narrative, Braine said: “I think they’re being controlled by an EU federalist class. I would go so far as to say a traitor class, people who are conspiring with foreign powers against the people of this country.”

Braine took over from Gerard Batten at the weekend after winning more than half the Ukip members’ votes in a four-way contest. He was nominated by Batten, and shares similar far-right views on Islam, which the former leader called a death cult.

Asked why he had questioned whether the public distribution of the Qur’an could fall foul of laws over incitement to violence, Braine said the UK needed to “look at the relationship between those verses and why some people seem to be motivated to go out and commit these acts”.

He dismissed the idea that a literalist reading of aspects of the Bible could also be problematic: “In Islam, over 1,400 years, we’ve seen expansionist conquests, jihad, over 500 battles in Europe. So I think it’s a very dangerous thing that you’re doing, trying to pretend that these two scriptures or religious traditions are equivalent.”

At a hustings event during the leadership race, Braine argued that there were now UK towns and cities which were effective no-go areas for non-Muslims. Asked at the press conference to give examples, he cited YouTube footage of “people being made to feel very uncomfortable in areas of east London”, but declined to give details.

Braine inherits a party bumping along at tiny levels in the polls, with much of its former support taken by the Brexit party of Ukip’s former leader Nigel Farage.

Announcing a new policy forum for members to suggest ideas, Braine insisted Ukip would remain relevant, and said the Brexit party could vanish if the UK left the EU on 31 October.

“I think that at that point the Brexit party will just disappear, like Vote Leave did, just gone,” he said. “I can’t see it continuing after that. Ukip’s different, we’ve been at it 27 years. The party has an embedded culture of old-fashioned, libertarian conservatives.”

Braine suggested Ukip could take part in a pro-Brexit electoral pact at a general election, saying his party did not have the resources to stand candidates in all 650 Westminster seats.

He also said the party could exert indirect influence, as in the case of Brexit: “If we get our policies right, if we manage to get through to people, and if our ideas enable us to apply pressure on the bigger parties, there is no reason why we can’t continue to get our policy implemented, whether we’re elected or not.”