Image copyright PA/Getty Image caption Theresa May and Enda Kenny discussed Stormont's political crisis on the phone on Monday night

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.

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.

McGuinness health

UK PM Theresa May and Irish Taoiseach 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.

Media playback is unsupported on your device Media caption How did Northern Ireland end up facing a second Assembly election in 12 months?

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.

The parties' fractured relationship will be debated at Stormont later in a motion tabled by the opposition parties.

"The public mood seems to be somewhere between apathy and anger," said Alliance MLA and former justice minister David Ford.

"If people don't want to vote for something different then they are consigning us to this ongoing mess."

TUV leader Jim Allister echoed that sentiment telling the BBC's Good Morning Ulster programme: "We cannot go on as we are."

"Unionism has nothing more to give to Sinn Féin; if that means a return to direct rule then so be it."

Also on Tuesday's 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.

Media playback is unsupported on your device Media caption What happens now the deputy first minister has resigned?

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.

Sinn Féin decided not to move a motion of no confidence in DUP Speaker Robin Newton over his handling of debates on the crisis, as the motion was vetoed by the DUP which used a petition of concern, which was originally designed to safeguard minority rights.

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.