A power-sharing executive will not be re-established at Stormont immediately after the election.
Instead, a review of the workings of the Good Friday Agreement and a further round of negotiations is expected to begin.
Meanwhile, an exit poll of 1,500 people has claimed that the Ulster Unionists and Democratic Unionists are neck-and-neck with 25% of people saying they had given their first preference votes to either party.
The survey, carried out for the Republic of Ireland's broadcasting station, RTE, suggested that Sinn Fein had secured 20% support with the SDLP getting 16% of first preferences.
Wednesday's poll was the first election in Northern Ireland to be held in November since 1965.