BBC News - Labour's union move a terrible risk, says Miliband's ex-adviser 5 September 2013 Last updated at 16:16 Ed Miliband is running "a terrible risk" in reforming Labour's relationship with unions, the party's former election co-ordinator has said. The GMB union has cut its funding to Labour by £1m, after Mr Miliband proposed ending automatic affiliation of union members to the party. Tom Watson, who left Labour's frontbench team in July, said he felt "great sadness" over the situation. Mr Miliband says changes will increase the number of active Labour members. Continuing disagreements between the party leadership and the unions look set to dominate next week's TUC annual conference in Bournemouth. Mr Miliband announced in July that he would end the automatic "affiliation" fee paid to Labour by three million union members, arguing that people should not give any money "unless they have deliberately chosen to do so." The changes would have "massive financial implications" for the party, he acknowledged, but could raise its membership from the current 200,000 to a "far higher number." Historic The announcement came after the Unite union, the party's biggest donor, was accused of signing up its members to Labour in Falkirk - some without their knowledge - in an effort to get its preferred candidate selected to fight the next election. Mr Miliband's actions angered union leaders, who are among the party's biggest financial backers. And, on Wednesday, GMB general secretary Paul Kenny announced that it would cut the affiliation funds it gives Labour from £1.2m to £150,000. Mr Watson, the MP for West Bromwich East, whose office manager was Unite's choice for the seat, quit his role as Mr Miliband's election co-cordinator over the row. Speaking about the GMB's decision, he told the BBC: "I feel a great sense of sadness. There is 100 years' history in the relationship between unions and the Labour Party. The decision by the GMB struck me as being quite historic. They are disengaging. They don't feel like valued partners any more. It's also a great worry for the Labour Party. That [union] link, though it has caused tensions, has sustained Labour through good years and bad. To lose that would be a shame. He added: "I don't speak for the other unions but my sense is the GMB is often considered as the union closest to the Labour Party, so if they have taken this historic decision there will be pressure in the other unions. I certainly wasn't aware we were going to have a trade union reform package announced when I was in the shadow cabinet, so it did seem a bit rushed to me and I genuinely think they got it wrong in Falkirk as well. Mr Watson called on the GMB to "reconsider" its funding cut. Following a meeting in Parliament with Mr Miliband, Mr Kenny called the Labour leader a "really decent bloke." He added: "He believes in what he's trying to do in reforming the party. It may have consequences. We have to see what comes in due course. I don't think people understand the consequences. Having the GMB point out what the possible implications are may focus people's minds.