Donald Trump hit out furiously today at the new status of “felon” conferred on him by a New York jury, whose guilty verdict made him the first former US president ever to become a convicted criminal.

A day after being found guilty of all 34 charges he faced, the ex-president painted himself as a victim of injustice in a rambling and often incoherent appearance at Trump Tower on Fifth Avenue in Manhattan, at which he labelled his opponents “fascists” and blamed his legal plight on Joe Biden.

Trump was unanimously convicted by a jury early on Thursday evening, after less than two full days of deliberations, of falsifying business records in a criminal hush-money scheme to influence the outcome of the 2016 election.

Related: ‘I’d enjoy seeing him go to prison’: voters react to guilty verdict in Trump trial

Entering an auditorium on Friday morning to cheers from his supporters, he set the tone immediately by revisiting one of his favorite populist election-campaign warnings.

He said: “If they can do this to me, they can do this to anyone.”

The event had been billed as a press conference, but Trump took no questions.

Instead, he lapsed into a 30-odd-minute monologue that featured hammered themes of his stump routine and that criticized all aspects of the process. The speech was peppered with falsehoods and conspiracy theories that threatened bad things to come if he is not returned to the White House this November, while also pivoting to key rightwing talking points such as immigration.

On people seeking refuge and asylum in the US, he said: “These are bad people. These are, in many cases, I believe, sick people. When you look at our country, what’s happening, where millions and millions of people are flowing in from all parts of the world, not just South America, from Africa, from Asia, from the Middle East, and they’re coming in from jails and prisons, and they’re coming in from mental institutions and insane asylums.”

Meanwhile, his legal team had already embarked on a counter-offensive to the criminal conviction, aimed at overturning Thursday’s verdict.

With the 2024 presidential election campaign propelled deep into uncharted territory, Todd Blanche, Trump’s attorney, went on national television to make a spirited though measured defense of his client, vowing to lodge an appeal.

The jury found that Trump falsified documents related to hush money paid to Stormy Daniels, shortly before the 2016 presidential election, to silence her story that she slept with him earlier in his marriage to Melania Trump.

Appearing on NBC, Blanche insisted Trump’s defense had not been given “a fair shake” during the trial.

“We’re going to appeal and we’re going to win on appeal,” Blanche told NBC Today’s Savannah Guthrie. “That’s the goal. The goal is … to appeal quickly and hopefully be vindicated quickly.”

Trump now faces the prospect of rewriting the record books further, if he were to be sent to jail when the judge, Juan Merchan, sentences him on 11 July, four days before the Republican national convention in Milwaukee, where Trump is scheduled to be officially anointed as the party’s presidential nominee for this November’s election.

Some analysts predict that the prospect of a custodial sentence has risen because of Trump’s repeated breaking of gag orders during the six-week trial and his condemnation of Merchant as “corrupt and conflicted” after Thursday’s verdict.

But Blanche played down that possibility, pointing to Trump’s advanced age and his previous lack of a criminal record.

The Manhattan district attorney, Alvin Bragg, who led the case against Trump and also was attacked by the former president, has yet to announce whether he will request a prison sentence.

Nothing in Trump’s demeanour on Friday suggested this was a prospect that worried him, as he embarked on a no-holds-barred, scatter-gun rhetorical assault on his enemies.

Trump pointedly linked his prosecution and the verdict with Biden, whom he labelled “the Manchurian candidate” and “the worst president in our history”, as well as “stupid” and “dishonest”.

“They are in total conjunction with the White House, the DoJ, just so you understand, this is all done by Biden and his people,” he said, referring to the legal team that led the prosecution and presumably Merchan, whom he called – among other things – “a tyrant”.

Biden had declined to offer any comment or reaction to the verdict by Friday afternoon. Ian Sams, spokesperson for the White House counsel’s office, said in a statement: “We respect the rule of law, and have no additional comment.”

The president’s re-election campaign team commented. Michael Tyler, the Biden campaign communications director, said: “No one is above the law. Donald Trump has always mistakenly believed he would never face consequences for breaking the law for his own personal gain.”

Trump and his campaign said that since the verdict, they have raised more than $30m.

Larry Sabato, director of the Center for Politics at the University of Virginia, said Trump’s false accusations that the case was orchestrated by Biden raised the spectre of further political violence at a time when Supreme Court rulings are awaited on the January 6, 2021 attack on the US Capitol by a mob trying to reverse the last presidential election result.

“The real concern here is not that Trump would be able to stir up his base and get loads more votes, because there aren’t loads more votes to get,” he said. “The real question is will Trump continue to feed this sense of persecution, making phony charges that Biden’s orchestrating all this.

“That’s not the way our system works. But he has ruined public confidence in our election system, and he’s now ruining public confidence in our judicial system. The man is the worst thing that has happened to American democracy in my lifetime.”

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