Len McCluskey, the general secretary of Britain's Unite Union says Labour lost its way during its 13 years in power leaving workers with fewer rights than many of their European counterparts.
He said Labour had no god-given right to exist and could not survive without union money. The challenge for the union was to try to influence Labour to put forward a radical alternative.
You can watch the full interview on BBC World News on Monday 26 March at 20:30 GMT and at and 0330, 0830 and 1530 GMT on Tuesday, 27th March and on the BBC News Channel on Tuesday 27 March at 00:30 BST and 04.30 BST.
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