Unionist opposition to an “economic united Ireland” and fears over a steady post-Brexit business decline are defining one of Northern Ireland’s most affluent areas this General Election.

Stephen Farry, from the cross-community Alliance Party, is engaged in a tight race with the DUP’s Alex Easton to win the seat vacated by a pro-Remain unionist in North Down.

It is branded the gold coast by some because of the grand houses which hug scenic Belfast Lough but also contains significant pockets of deprivation.

Mr Easton said many residents were most concerned about safeguarding the Union with Great Britain following Prime Minister Boris Johnson’s proposed Brexit deal.

DUP candidate for North Down Alex Easton, left, meeting constituents on the doorstep with his party leader Arlene Foster, right (Liam McBurney/PA)

He said: “It is totally unacceptable to have an economic united Ireland and that is what that would cause.

“That is just not acceptable to the people of Northern Ireland.”

Irish nationalists want to ensure checks on goods entering the EU single market do not entail physical infrastructure on the land border between Northern Ireland and the Republic.

Mr Johnson’s proposed Brexit deal would involve extra administration on goods travelling from the rest of the UK to Northern Ireland to avoid a hard frontier on the island of Ireland.

Mr Easton said widespread parts of North Down harboured concerns about the Brexit deal.

He said: “It is going to affect trade, it is going to cause a border down the Irish Sea and it is quite a serious thing that they have negotiated.”

North Down contains a series of dormitory towns and villages for Belfast workers.

2010 General Election declarations
Lady Sylvia Hermon has stepped down this election, leaving a race between parties to replace her in North Down (PA)

It has a reputation for electing independent MPs, most recently Lady Sylvia Hermon, the widow of a former Royal Ulster Constabulary chief constable and a former Ulster Unionist who left the party over its ties with the Conservatives.

Over recent elections, the DUP cut Lady Sylvia’s lead considerably and will be hoping for success this time round.

Mr Easton sat on Stormont’s health committee when devolution was operating.

The NHS in Northern Ireland has experienced significant pressures over recent years, with no powersharing ministers to take decisions on rationalisation of services.

Mr Farry is the Alliance Party’s deputy leader and advocates a People’s Vote in a bid to overturn the referendum result.

He said: “It is important that we create a deal that protects the Northern Ireland economy as we go forward.

Alliance candidate for North Down Stephen Farry signing a pledge to stop Brexit with Doire Finn from Our Future Our Choice (Liam McBurney/PA)

“People’s livelihoods are at stake, people’s opportunities.

“We want people to stay in Northern Ireland and to build their futures here.

“Already Northern Ireland has a sad track record of exporting too much of its talent.

“A lot of work has been done to try to build the economy here over the past number of years and to keep people working in our society and building their futures here.

“I would fear that with Brexit that would go into reverse and we would end up losing a lot more people and with that we go into steady decline, which is very sad.”

The other candidates running in North Down are Alan Chambers of the Ulster Unionist Party and Matthew Robinson of the Conservative Party.