DUP leader Gavin Robinson has appealed for “greater cohesion” among unionists following General Election results which saw his party suffer damaging defeats in North Antrim and Lagan Valley.

Following the election Sinn Fein has emerged for the first time with the largest representation among Northern Ireland parties at Westminster.

The republican party’s president Mary Lou McDonald has now urged Sir Keir Starmer to “embrace the right of Irish self-determination and constitutional change toward Irish reunification”.

However, Mr Robinson dismissed suggestions that the election result strengthened the argument towards Irish unity, stating there “has been no groundswell of support for a border poll”.

The DUP suffered a bruising set of results, losing its Westminster seat in North Antrim, which has been held by the Paisley family for 54 years.

Traditional Unionist Voice (TUV) leader Jim Allister, a fierce DUP critic, won the seat from Ian Paisley by 450 votes.

The Alliance Party’s Sorcha Eastwood also had a historic result as she triumphed in the DUP stronghold of Lagan Valley, the seat formerly held by party leader Sir Jeffrey Donaldson.

Donaldson did not stand for re-election in Lagan Valley, having stepped down as leader in March when he was charged with historical sexual offences, charges he denies.

The DUP has been under fire from unionist rivals amid claims it oversold a Government package of measures on post-Brexit trading arrangements that the party used to justify the end of its two-year boycott on devolution at Stormont in January.

Northern Ireland’s largest unionist party also lost out in South Antrim where former Stormont health minister, Robin Swann of the Ulster Unionist Party, defeated Paul Girvan.

One bright spot in a disappointing night was when DUP leader, Gavin Robinson, held off the challenge of Alliance Party leader Naomi Long in East Belfast.

In the last result of the night, veteran DUP representative Gregory Campbell narrowly held on to his East Londonderry seat by just 179 votes, having seen his previous majority of almost 10,000 slashed.

This left the DUP with five seats, down from the eight it won in 2019.

Mr Robinson conceded the results had not been what his party had wanted.

He said: “We must be realistic about the significant job of work ahead to get unionism into a stronger and more strategic position.”

The DUP leader pointed out that unionism had retained the same number of seats as in 2019, although now split among different parties and independent unionist Alex Easton, who won in North Down.

The DUP and TUV did not run a candidate against Mr Easton.

There has been no groundswell of support for a border poll as some within Sinn Fein would claim

Mr Robinson added: “We can never again see a situation where pro-union voters are so divided that seats are lost to those who will not promote the union.

“I am pledged to work for greater cohesion within the pro-union movement.

“In North Down it has been demonstrated what can be achieved with co-operation, allied to a strong work ethic.

“Having unilaterally taken the decision to support Alex Easton, as well as Diane Armstrong in Fermanagh/South Tyrone, there is no doubt that the unionist influence can be advanced.

“In truth the result in North Down demonstrated what is possible when unionists work together and the result in Lagan Valley demonstrated the cost of division.”

The DUP leader insisted the combined nationalist vote had not grown since 1998.

He said: “There has been no groundswell of support for a border poll as some within Sinn Fein would claim.”

After all 18 constituencies were declared, it was confirmed Sinn Fein had repeated its success in the Northern Ireland Assembly and local government elections of the previous two years by emerging as the largest party.

The party retained its seats in Mid Ulster, North Belfast, Newry and Armagh, South Down, West Belfast and West Tyrone.

Former nursing union boss Pat Cullen also held Fermanagh and South Tyrone for Sinn Fein with an increased majority.

Ms McDonald said the result creates “a major opportunity to improve relations between Britain and Ireland”.

She said: “Sinn Fein is determined to build a constructive relationship with the new Labour government.

“We look forward to working positively with British Prime Minister Keir Starmer on the many shared priorities for Ireland and Britain during this historic time of renewal.

“After 14 years of Tory rule, marked by dysfunction and chaos, they crudely undermined the Good Friday Agreement during Brexit, harming citizens and communities.

“They also abandoned co-operation with Dublin, causing significant damage.”

The British Government must embrace principles of rigorous impartiality and the right to self-determination and constitutional change

She added: “The new Labour government now has a huge opportunity to reset relations with the Irish Government and the power-sharing (Stormont) Executive, where First Minister Michelle O’Neill will work to restore effective co-operation.

“We expect the new Prime Minister to uphold the Good Friday Agreement, which Labour helped deliver, ensuring its political, legal and constitutional guarantees are respected.

“This includes respecting all our national identities, political allegiances and working together to defend peace and build on reconciliation efforts.

“The British Government must embrace principles of rigorous impartiality and the right to self-determination and constitutional change toward Irish reunification.”

It was a mixed night for the cross-community Alliance Party, despite Ms Eastwood’s stunning success in Lagan Valley.

In North Down, deputy leader Stephen Farry lost his seat to Mr Easton and leader Ms Long failed in her bid to unseat Mr Robinson in East Belfast.

The Ulster Unionist Party is returning to Westminster for the first time since 2017 following Mr Swann’s comprehensive victory in South Antrim.

However, retired Army colonel Tim Collins, who ran for the UUP in North Down, blamed voters being more interested in “potholes and hedges” than international affairs after conceding defeat.

The SDLP retained the two seats held in the last parliament by its leader, Colum Eastwood, in Foyle, and deputy leader, Claire Hanna, in South Belfast and Mid Down.

Mr Eastwood said: “I have to say I’m delighted to see the back of the Tory government.

“Fourteen years of destroying our public services, 14 years of destroying the economy, destroying family finances is now gone.”