The Northern Ireland Secretary is holding talks with the political parties to discuss the crisis caused by the Renewable Heat Incentive scandal.
James Brokenshire is meeting Sinn F3éin on Wednesday morning, and plans to have talks with the main parties, and the justice minister, within 24 hours.
Martin McGuinness stepped down as deputy first minister in protest at the handling of the botched energy scheme.
Mr Brokenshire said his move means an assembly election is “highly likely”.
The prime minister and taoiseach (Irish prime minister) also pledged to do what they can after speaking by phone on Tuesday night.
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