- Video report by ITV News Europe Editor James Mates
A leading group of MEPs responsible for UK-EU negotiations have "grave concerns" about Boris Johnson's new Brexit proposals.
The European parliament's Brexit Steering Group (BSG), which includes prominent MEPs involved in Brexit talks, such as Guy Verhofstadt, said Mr Johnson's plan cannot be backed "in their current form". This scepticism was also shared by European Council president Donald Tusk, who said the EU was "open but unconvinced".
Mr Johnson's new plan had altered Mrs May's withdrawal agreement deal with the EU, promising a new solution to the Irish backstop and border.
However, the BSG statement said the proposals do not address "the real issues" around customs and border checks between Northern Ireland and the Republic.
It added: "The proposals do not address the real issues that need to be resolved if the backstop were to be removed, namely the all-island economy, the full respect of the Good Friday Agreement and the integrity of the single market.
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"While we remain open to workable, legally operable and serious solutions, the UK's proposals fall short and represent a significant movement away from joint commitments and objectives."
It added: "In summary, the BSG has grave concerns about the UK proposal, as tabled. Safeguarding peace and stability on the island of Ireland, protection of citizens and EU's legal order has to be the main focus of any deal.
"The UK proposals do not match even remotely what was agreed as a sufficient compromise in the backstop."
European Commission president Jean-Claude Juncker spoke to Leo Varadkar about the latest Brexit proposals on Thursday during which he "reaffirmed his unwavering support for Ireland".
A Commission statement said that while President Juncker confirmed the UK has made some progress, a number of problematic points remain in the proposal, on which further work is needed.
"President Juncker emphasised that the governance of the backstop should be stable and predictable," added the statement.
"He reiterated that the Withdrawal Agreement must have a legally operational solution now, and cannot be based on untried arrangements that would be left to negotiation during the transition period."
The statement will come as a blow to the prime minister, who is hoping to secure a deal with the EU by October 17, in order for the UK to leave by October 31.
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Speaking in the House of Commons on Thursday, Mr Johnson said his new Brexit proposals are a "genuine attempt" to break the impasse and secure a deal with the EU.
He defended his new Brexit plan which has devised alternative arrangements over the Irish backstops and customs checks between Northern Ireland and the Republic.
Speaking in the Commons, Mr Johnson said: "This Government's objective has always been to leave with a deal and these constructive and reasonable proposals show our seriousness of purpose.
"They do not deliver everything that we would've wished, they do represent a compromise, but to remain a prisoner of existing positions is to become a cause of deadlock rather than breakthrough.
"So we have made a genuine attempt to bridge the chasm, to reconcile the apparently irreconcilable and to go the extra mile as time runs short."
The prime minister has previously said he wants to secure a deal before the EU summit on October 17, so the UK can leave by October 31.
But Irish premier Leo Varadkar said Mr Johnson's Brexit plans "fall short in a number of aspects".
Mr Varadkar said he welcomed the written proposals but in regards to the Irish border, particularly custom checks, it would have to be "reflective of the views of the whole of the population of Northern Ireland".
He continued: "We need to explore in much more details the customs proposals being put forward as it's very much the view of the Irish government and people of Ireland, north and south, that there shouldn't be a customs check points or tariffs between north and south."
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However Mr Johnson's opponents in the Commons were unmoved by his new Brexit proposals, with Jeremy Corbyn, Lib Dem leader Jo Swinson and the SNP's Ian Blackford all rubbishing the new proposals.
Mr Corbyn labelled the new proposals as a "Trump-deal Brexit" which threatens workers rights and regulations.
He said: "These proposals would lead to an even worse deal than that agreed by the former prime minister."
"No Labour MP could support such a reckless deal that will be used as a springboard to attack rights and standards in this country."
Ms Swinson urged Mr Johnson to visit the Northern Ireland border and listen to those in the community.
Mr Blackford said the deal was unworkable for Scotland, and again called on Mr Johnson to resign.
He said: "The SNP will do everything possible to secure an extension and to stop a no-deal Brexit, so I say to the Prime Minister, be warned, secure an extension or resign, if not the SNP stand ready to bring this Government down."
There has been support on the backbenchers for Mr Johnson's plans, including from notable Brexiteers such as Mark Francois and Sir Bill Cash.
Mr Francois, the deputy chairman of the pro-Brexit European Research Group, said: "May I commend the Prime Minister's emphasis on a future free trade as his desired end state which is what many of us have wanted all along."
However former prime minister Theresa May looked on at Mr Johnson inquisitively during the Commons sitting, suggesting some MPs still need convincing when it comes to backing this new Brexit proposal.
Under Mr Johnson's proposals, Northern Ireland would remain in the EU single market rules for trade in goods, but leave the customs union with the rest of the UK as a "fair and reasonable compromise".
The Irish Taoiseach said the proposals "do not fully meet the agreed objectives" of the backstop, while Mr Juncker said there were "problematic points".
Brexit Secretary Stephen Barclay sought to defend the proposals in a round of interviews on Thursday morning.
“We’re being very clear that we stand by our commitments to the Belfast Good Friday Agreement,” he told BBC Radio 4’s Today programme.
“There will be no infrastructure on the border.”
As to the necessity of checks, he argued that “most smuggling operations aren’t actually addressed at a border”, with a heavy reliance instead on intelligence-sharing.
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Even if the Mr Johnson gets the support of EU leaders for a deal, he must get it through a Parliament that has so far been hostile to Brexit proposals.
Nationalists in Northern Ireland also expressed anger over a proposal requiring the suspended Stormont Assembly to approve the new arrangements, with a vote every four years.
Sinn Fein argued that it would effectively hand a veto to Mr Johnson’s allies, the DUP, who have a majority in the assembly.
Under the plan, the arrangements would start in 2021 at the end of the proposed transition period if there was no long-term trade agreement at that point and would continue until one was in place.
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