Britain's Prime Minister Theresa May speaks during a press conference inside 10 Downing Street in London, Thursday, Nov. 15, 2018.
Britain's Prime Minister Theresa May speaks during a press conference inside 10 Downing Street in London, Thursday, Nov. 15, 2018.

British Prime Minister Theresa May is promising to fight for approval of the draft agreement for Britain to withdraw from the European Union, saying a rejection would put Britain on "a path of deep and grave uncertainty."

May's already tough task of convincing parliament to approve the deal suffered a setback earlier Thursday when her Brexit Secretary Dominic Raab and pensions minister Esther McVey resigned.

Britain's Prime Minister Theresa May, makes a statement outside 10 Downing Street, in London, Britain, Nov. 14, 2018.
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Their resignations came just more than 12 hours after May announced her Cabinet had agreed to terms of the deal, leaving her with the task of convincing a majority in parliament to approve the agreement.

May told reporters she understood Raab's and McVey's unhappiness with her agreement, but said it was the "best deal for the United Kingdom."

Raab specifically objected to a key provision setting up a customs union that would eliminate the need for a hard border between Britain's Northern Ireland and EU member Ireland while Britain and the EU work on a new trade deal.  

He said not having a firm end date for such an arrangement would leave Britain without democratic control over laws governing its territory, and would "severely prejudice" the future trade talks.

McVey said in a letter that it is “no good trying to pretend to (voters) that this deal honors the result of the referendum when it is obvious to everyone that it doesn't.''

Britain's Prime Minister Theresa May delivers a speech outside 10 Downing Street in London, Nov. 14, 2018.
British Cabinet Backs Brexit Deal After Marathon Meeting
British Prime Minister Theresa May scrambled Wednesday to sell to her Cabinet a draft Brexit divorce agreement British negotiators concluded after months of wrangling with their European Union counterparts. After a five-hour Cabinet meeting, Britain’s beleaguered leader got the backing of her ministers.One-third of the Cabinet spoke out against the deal, however, and the draft agreement had to be approved on a majority vote rather than reached by consensus.

May was dealt another blow when leading pro-Brexit lawmaker Jacob Rees-Mogg called for a vote of no-confidence in the prime minister.
Rees-Mogg said outside Parliament the deal `is not Brexit'' because it would possibly leave Britain in a customs union with the EU for an indefinite period.

Speaking Thursday in parliament, opposition Labour Party Leader Jeremy Corbyn called the draft agreement a “huge and damaging failure.”

May defended the deal earlier, telling lawmakers it would mean Britain would leave the European Union “in a smooth and orderly way” and allow it to regain control of its borders, law and money, while protecting jobs and enhancing the security of the country.

The British pound dropped sharply in value against the U.S. dollar after Raab’s resignation.

Victor Beattie contributed to this report.