The taoiseach (Irish prime minister) is expected to ask Irish President Michael D Higgins to dissolve the current Dáil (lower house of the Irish parliament) later.
Under Irish law, once the Dáil is dissolved an election must be held within 30 days.
Earlier this week, Simon Harris indicated a preference for a polling day in the Republic of Ireland's general election on 29 November.
He is the leader of Fine Gael and heads a coalition government alongside Fianna Fáil and the Green Party.