The head of the UK's largest trade union has warned that Ed Miliband has yet to "close the deal" with workers, days after it was cleared of vote-rigging in Falkirk.
Len McCluskey, of Unite, said the Opposition leader had a challenge ahead of him to convince working people that the Labour Party still had their interests at heart.
Mr McCluskey also offered Mr Miliband some breathing space, suggesting Unite would not immediately follow the GMB path of withdrawing funding to the party.
Asked if Unite intended to cut its affiliation funds, he said: "No. I understand exactly what Paul (Kenny, GMB general secretary) has done."
Mr McCluskey who is a "close friend" of the GMB chief, said that Unite would "examine the proposals that are being put forward by Ed" before making a decision on party affiliation.
He said, however, that GMB's decision to cut the donations it gives Labour from £1.2 million to £150,000 from next year meant implications for all trade unions which "will have to examine where they stand in relation to the affiliation".
The Unite chief, who has consistently said he welcomed Mr Miliband's suggestions to review Labour's relationship with the trade unions, added a word of warning, telling him to be careful what he wishes for.
Mr McCluskey rubbished suggestions that the union had had a hand in determining the outcome of an investigation by Labour into claims it had rigged the selection of a party candidate in Falkirk after demands were made for the report to be published.
Instead, Mr McCluskey said there was no need for an apology after his party was cleared of any wrongdoing.
He added: "As leader he will take us into our election and he will have my support and Unite's support to do that. He is the guy we support but his challenge is to make sure that Labour demonstrates to ordinary working people ... he still has to close the deal with ordinary people."