Deputy Labour leader Harriet Harman will issue a plea for unity to union leaders at the annual TUC gathering.
Ms Harman will urge TUC members to unite behind Ed Miliband's plans to reform their historic links with the party, or risk a Tory general election victory.
Her speech comes amid ongoing hostility surrounding the proposed changes, and the continued fallout from the Falkirk selection-rigging scandal.
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Leicester City players have been celebrating their Premier League title after Spurs drew with Chelsea on Monday night.
Tonight western and northern areas will remain a little breezy with a few showers at times.
Leicester are Premier League champions after Tottenham conceded a two-goal lead in a bad-tempered 2-2 draw at Chelsea.