UPDATE 1-Sinn Fein establish clear lead in opinion poll ahead of Irish election

Irish nationalists Sinn Fein have surged to the top of an opinion poll five days ahead of an election in Ireland that looks set to be a major breakthrough for the former political wing of the Irish Republican Army.

An Irish Times/ Ipsos MRBI poll published on Monday found support for left-wing Sinn Fein at 25%, making them a clear leader, with support for center-right Fianna Fail at 23%. Support for governing Fine Gael was 20%. The opinion poll found that satisfaction with the government had slumped, from 27% at the beginning of the campaign to 21% on Monday.

Approval for both Prime Minister Leo Varadkar and his main rival Fianna Fail leader Micheal Martin also fell, with Martin's rating falling by three points to 30% and Varadkar's by five points to 30%. Despite the poll, Sinn Fein is unlikely to emerge as the largest party as it is running only 42 candidates, which is around half the number of candidates being fielded by both Fine Gael and Fianna Fail.

Sinn Fein would need to get almost all 42 elected to the 160-seat chamber to give it a shot at emerging as the largest party. Getting such a return would be difficult for any party, analysts say. Ireland's proportional representation system also favors parties running more than one candidate in larger constituencies.

Earlier on Monday, Ireland's national broadcaster RTE reversed a decision to exclude Sinn Fein leader Mary Lou McDonald from a televised debate scheduled for Tuesday evening. The broadcaster had planned to restrict the debate to Varadkar and Martin, the leaders of the two parties it considered most likely to lead the next Irish government based on empirical data.