16 January 2017 Last updated at 17:18 GMT
Mr Murphy said the party had been "stretched to the limits" by their former partners in government, the DUP. (Democratic Unionist Party).
Sinn Féin's Conor Murphy says it's time for an election as the deadline passes for Secretary of State James Brokenshire to call one, after the party refused to re-nominate a deputy first minister.