The former Tory Cabinet minister handed a second defeat to Theresa May after his Article 50 Bill amendment passed through the Upper Chamber with a majority of 98.
The 83-year-old, who was sacked from his Government roles after the intervention, had previously warned quitting the European Union was the “most disastrous peacetime result in this country”.
Discussing his sacking on BBC Radio 4’s Today programme, Lord Heseltine bemoaned the criticism of Remainers who are attempting to argue against Britain’s EU divorce.
He claimed Nigel Farage, who claimed he would challenge a narrow victory for Remain with second referendum demands, would never have faced the same treatment as pro-European activists.
Lord Heseltine received a torrent of social media abuse after he vowed to continue Brexit battle
Why is it alright for Brexiteers to go on fighting – why shouldn’t people like me argue in the other camp?
“Since the referendum I have been meticulous in not talking to the press,” Lord Heseltine said, explaining his decision to challenge the Government.
“They’ve been on to me all the time – from all over the world – and I have said, ‘Look, No I’m not doing it’, because I wasn’t in the business of trying to continue a running battle.
“Brexit now means negotiating our severance with Europe – that I have accepted. But the point comes in life when you have to do what you believe to be right.
“Saying that somehow or other parliament couldn’t have enshrine in the statute a commitment to involve parliament – the sovereign body of our country – was too much for me.”
The former Conservative deputy leader claimed “every European parliament” will have to “ratify” any new deal, adding British politicians should have the same right to do the same.
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Then challenged on whether he is trying to “subvert the will of the people” by the programme’s host Mishal Husain.
“I said clearly in the Lords yesterday no-one has the first idea of what the circumstances will be in two years time,” he added.
“No-one even knows what governments are going to be in Europe, whom we’ll be negotiating with and no-one knows what British public opinion will be like in two years time.
“There is a massive uncertainty – I say is the mandate of the referendum for all time?
“Look, let’s be frank, Nigel Farage was saying before the result, when he thought he was going to lose, that there needs to be another referendum. In Scotland, they are already talking of another referendum.
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“I know these Brexiteers backwards, I lived with them in government and opposition for many years now, and they never give up. So, why is it alright for them to go on fighting – whatever the opinion happened to be – why shouldn’t people like me argue in the other camp?”
He concluded by predicting Mrs May will face a tough negotiation period with her European counterparts, because they know Brexit “won by a narrow majority” and a “great deal of the battle” was based on issues from outside the EU.
Lord Heseltine’s comments sparked outrage on social media, with Brexit supporters slamming the peer’s comments.
One Twitter user wrote: “Heseltine proving the adage ‘there is no fool like an old fool’.”
Remoaners Club: These people hate Brexit! Mon, January 16, 2017
Remainers are finding it hard to accept Brexit.
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Another claimed: “Heseltine telling it like it is, albeit a parasite fearful of losing his £900,000-a-year EU subsidy.”
Others predicted his sacking from his Government advisory roles could further hamper Mrs May’s Brexit negotiations.
“If Heseltine is now free for three or four days a week after being sacked, won’t that mean he has more time to cause Mrs May trouble on Brexit?” One user wrote.
While others predicted the sacking could be a sign of Mrs May acting in “fear and acknowledges vulnerability”.