In what is an increasingly fraught and divisive debate, many are predicting that the deal will be voted down, leaving the prospect of a no-deal Brexit as the March 29th deadline for leaving the European Union approaches.
In a wide ranging interview with Premier, Welby reiterated his concerns that a no-deal Brexit would impact the poorest and most vulnerable in society.
The head of the Church of England recently spoke of a no-deal outcome being "not only a political and practical failure, but a moral one" and in the interview he went further to say: "The burden of proof is on those that are arguing for no deal, to show that it will not harm the poorest and most vulnerable.
"They are close to the heart of God in Jesus Christ, so how we care about them and how our politics affects them is a deeply moral issue."
When asked what his prayer for the Prime Minister and other Members of Parliament would be, he stated: "Politicians have one of the hardest jobs in the world, it is deeply diffcult, and we need to pray for them.
"When I pray for Theresa May and for all of our politicians, with genuine affection and respect, I pray for wisdom, courage and strength for them and their families.
"I pray that they would be blessed. They are entrusted with more responsibility than any of us could cope with."
MPs will vote in Parliament tomorrow on Theresa May's plans.
The Prime Minister is warning that no Brexit is more likely than no-deal if they don't support her proposals.
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