Sinn Féin has made significant gains in the Northern Assembly elections on the back of an increased republican vote, dramatically narrowing the gap between it and the Democratic Unionist Party.

As counting continued late on Friday night , the DUP appeared on course to remain as the largest party in Northern Ireland and in line to nominate for First Minister.

Sinn Féin, however, has significantly reduced the gap between it and the DUP.

But whether Stormont can be restored in the short term remains problematic, with Sinn Féin repeating that it will not enter a new Northern Executive with Ms Foster as First Minister.

Its Northern leader Michelle O’Neill again insisted that Ms Foster cannot be in the Executive until the public inquiry into the renewable heat incentive (RHI) scheme is completed. The DUP in turn has insisted it is standing by its leader.

The biggest political casualty of the election last night was the Ulster Unionist Party leader Mike Nesbitt, who announced that he is to resign when a successor is chosen.

Mr Nesbitt had encouraged the transferring of votes to the SDLP to “strengthen the middle-ground” and had predicted that his party would win more seats than the DUP.

Last May the UUP won 16 seats but late last night it was in danger of seeing its representation reduced to nine seats or possibly less.

‘More polarised’

Alliance had a strong election, increasing its vote by more than two percentage points to 9.1 per cent and on course to hold the eight seats it won last May. This represents a net gain, as the next Assembly is reduced from 108 to 90 seats.

In the Assembly election last May the DUP was almost 36,000 votes and more than five percentage points ahead of Sinn Féin, winning 38 seats to Sinn Féin’s 28.

In this election, however, Sinn Féin has reduced the difference to less than 1,200 votes, with the DUP taking 28.1 per cent of the vote and Sinn Féin 27.9 per cent.

The DUP appeared on course to win between 28 and 32 seats, with a number of fifth and final seats in the balance, while Sinn Féin could win between 25 and 28 seats.

There was an outside possibility the parties could be neck and neck.

Last May close to 704,000 people voted, while this time there was a surge in turnout to almost 813,000, which benefited Sinn Féin particularly.

With a number of hard-to-call contests continuing for the final fifth seats, the SDLP seemed set to win between nine and 11 seats, having won 12 seats last May. It lost one of its veteran MLAs in West Belfast, the former minister and senior peace process negotiator Alex Attwood.

RHI debacle

The parties now have three weeks to form a new Executive. If that is not possible in that short timeframe, then the Northern Secretary James Brokenshire would be due to call fresh elections.

The expectation, however, is that some mechanism will be found to buy more time to test if a deal can be done between the DUP and Sinn Féin.

Despite Sinn Féin’s demand that Ms Foster step aside, DUP Lagan Valley MP Sir Jeffrey Donaldson said she still had the support of his party.

“”People were voting for parties to get back into government to sort things out. I recognise Sinn Féin has a big mandate. The DUP has a big mandate . . . I would urge parties not to get in to setting preconditions,” he said.