THE Democratic Unionist Party unexpectedly became kingmakers after the 2017 General Election, as their ten MPs keep a minority Tory government in power.

In response to the Brexit deal being secured in Brussels, the DUP said they will not vote in favour. So who are they and what do they stand for?

Follow our live blog for latest updates from Saturday's emergency Commons sitting to vote on Boris Johnson's Brexit deal

3 DUP leader Arlene Foster and deputy leader Nigel Dodds arrive in Downing Street Credit: PA:Press Association

Who are the Democratic Unionist Party?

Founded by Protestant firebrand Ian Paisley, the Democratic Unionist Party was once a fringe party but is now the largest in Northern Ireland, with a narrow electoral edge over republicans Sinn Fein.

Led by Arlene Foster, they are staunchly pro-union and pro-Brexit, making them a natural fit for a deal with the Tories.

Their campaign manifesto included retaining the "triple lock" on pensions and cutting VAT for tourism businesses.

The DUP also support a nuclear deterrent, which puts them at odds with anti-Trident Jeremy Corbyn.

But the DUP have conservative views on issues such as gay marriage and abortion - which could make implementing May's social policies more difficult.

They have also been criticised in the past for their links to members of violent loyalist paramilitary groups like the UVF.

Johnson has reportedly been handed a lifeline by the Democratic Unionist Party in the Irish backstop battle.

It was said the DUP has agreed to a move that could pave the way for a Brexit deal.

The Times reported the party accepted some changes that would see Northern Ireland sticking to some European Union rules post-Brexit.

But it would be a new deal to replace the hard Irish backstop, a sticking point for many in the Brexit negotiations.

The paper claimed the DUP, the biggest party in Northern Ireland, had also privately said it would drop its objection to regulatory checks in the Irish Sea.

3 The DUP is led by Arlene Foster in Northern Ireland and Sir Jeffery Donaldson in Westminster Credit: PA:Press Association

What deal was struck with the DUP?

The DUP believes it has been betrayed by Boris Johnson's Brexit deal.

The party accused the PM of

undermining the union and the “professed sanctity” of the Good Friday Agreement.

The Tories’ Northern Ireland allies protesting about the agreement in three areas – customs, consent and VAT.

The DUP signed up to the prime minister’s proposals last week because they promised a Unionist veto at Stormont, allowing it to block – or later remove – alignment with EU customs and single market rules.The new deal removes that veto, exercised by just 30 votes in the 90-member Northern Ireland Assembly, and replaces it with consent for barriers in the Irish Sea with just a simple majority.

As Johnson outlined his deal in Parliament today, a fuming Nigel Dodds of the DUP said that Boris’ deal was not Brexit “for the whole of the UK” and said it would “drive a coach and horses through the Belfast agreement”.

The Northern Irish party - previously allies of the Tories - have vowed to vote against it this afternoon.

He said “no British PM” could agree to such terms to divide the UK, and that any divisions should be done with the consent of the Northern Ireland assembly.

DUP MP Jim Shannon shouted at the PM: "Sell out! Treachery! Betrayal!”

Who is DUP leader Arlene Foster?

Arlene Foster, 46, is Assembly Member for Fermanagh and South Tyrone and the leader of the Democratic Unionist Party.

She took over as First Minister of Northern Ireland last year after Peter Robinson stood down.

But the devolved Stormont government's collapsed in January amid a renewable energy fiasco.

The region has been directly governed from Westminster as repeated efforts to hatch a new power sharing deal failed.

Born in Enniskillen and raised in Dernawilt, County Fermanagh, she is the daughter of a police reservist who survived an assassination attempt by the IRA during the Troubles.

As a teenager she was on a school bus that was bombed by the IRA. Her pal was seriously injured.

Mrs Foster, a graduate of Enniskillen Collegiate Grammar School and Queen's University Belfast, has three children with husband Brian.

3 Arlene Foster, 46, is Assembly Member for Fermanagh and South Tyrone and the leader of the Democratic Unionist Party Credit: Getty Images - Getty

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What has Arlene Foster said about the Irish border and Brexit?

Theresa May seemed on the brink of agreeing a deal with Brussels on the first stage of Brexit negotiations, allowing talks to move to trade and the future relationship.

One sticking point was the frontier between the Republic of Ireland and Northern Ireland post-Brexit, with all sides keen to avoid the return of a "hard border".

A leaked draft appeared to show the UK had vowed to ensure "continued regulatory alignment" with the EU so as not to undermine the Good Friday Agreement.

The Dublin government claimed it as a victory, while Scottish First Minister Nicola Sturgeon and Welsh leader Carwyn Jones said it meant other parts of the UK could stay in the single market.

While Mrs May was meeting EU Commission chief Jean Claude-Juncker, the DUP made a statement that kiboshed what had seemed a done deal.

Mrs Foster said Northern Ireland must leave the EU on the same terms as the rest of the UK and she would not accept anything else.

The DUP had threatened to pull out of the confidence and supply deal if Theresa May caved into demands from Ireland and the EU.

Mrs Foster has previously accused the Irish government of hijacking Brexit negotiations to promote a united Ireland.

On 14 November, as Theresa May prepared to address her Cabinet with her agreed Brexit deal, Mrs Foster warned she won't accept a Brexit deal that treats Northern Ireland differently to the rest of the UK.

She rejected suggestions Northern Ireland could remain in the single market and customs union in a special arrangment to keep the border open.

That could mean "a border in the Irish Sea" - which is unacceptable to the DUP and Tory Brexiteers.

Ireland’s PM, Leo Varadkar, warned he would veto any progress in Brexit talks unless the UK came up with proposals to avoid a hard border with Northern Ireland.

DUP leader Arlene Foster demands Northern Ireland leave EU on same terms as the UK in Brexit

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