The UK and Irish prime ministers have urged politicians in Northern Ireland to be “respectful” during the election campaign.
NI Secretary James Brokenshire was legally obliged to call for the 2 March vote on Monday after the executive collapsed over a botched green scheme.
Stormont was plunged into crisis after the resignation of Martin McGuinness as deputy first minister last week.
Theresa May and Enda Kenny discussed the crisis by phone on Monday night.
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The catalyst was the Renewable Heat Incentive (RHI) scheme, which is likely to cost taxpayers £490m.
But the row over the scheme has resurfaced a range of other issues, including the Irish language and gay rights, which divide the Democratic Unionist Party (DUP)/Sinn Féin power-sharing executive.
MLAs will be back at Stormont later as preparations begin for the election.
UK PM Theresa May and Irish Taioseach Enda Kenny know a bitter election battle between Sinn Féin and the DUP will drive the parties further apart, reducing the chances of any agreement after the poll, which is why they have urged all sides to show respect during the campaign.
They also repeated their desire to see the institutions established under the Good Friday Agreement operating effectively.
They want a fully functioning executive in place as soon as possible after the election, which is a big ask given the gulf which now exists between the DUP and Sinn Féin.
Their fractured relationship will be debated at Stormont on later in a motion tabled by the opposition parties.
Also on the agenda, which is being set by the SDLP and Ulster Unionist party, will be a debate on the flawed Renewable Heat Incentive scheme.
Sinn Féin is unlikely to take part as it is understood its members will not be returning to Stormont before an election.
Meanwhile, Martin McGuinness is expected to announce in the coming days if he plans to stand in the election or will be stepping down due to his poor health.
He resigned last Monday after DUP leader Arlene Foster refused to stand aside as first minster while an investigation was carried out into RHI.
Mrs Foster was the minister in charge of the RHI scheme when it was set up in 2012.
It was designed to encourage businesses to switch from fossil fuels to more environmentally friendly energy sources. But subsidies were overly generous and initially there was no cap on the payments.
As they hold a joint office, Mr McGuinness’ resignation automatically put the DUP leader out of her job.
His resignation triggered a seven-day period whereby if a deal was not reached, an election would have to be called.
In a dramatic day at Stormont on Monday, Sinn Féin did not nominate a deputy first minister to replace Mr McGuinness, causing the devolved Stormont institutions to fall.
In last May’s election, the DUP and Sinn Féin were the largest and second largest parties elected. In this snap election, there will be a fall in the number of Stormont seats from 108 to 90.
Northern Ireland’s 18 constituencies will return five MLAs (Members of the Legislative Assembly) each, not six as has previously been the case. The number of MLAs has been cut in order to reduce the cost of politics.