Labour stops opposition money
Labour are in such debt that it will probably damage their ability to fight the next election. The Labour party know this so they are trying to stop opposition parties from spending and raising more money than the Labour party can.
There is to be a limit on how much can be spent on election campaigns. While this would be a good thing Labour are only doing it because they are facing serious financial difficulties and probably couldn’t fight an effective campaign if there was an election right now.
There will also be a cap of £50,000 on individual donations which will hurt the Conservatives much more than Labour who have decided not to put a cap on donations from unions who give Labour millions and effectively stop them from going bankrupt.
Trade union donations should also be capped at the same as individual donations but that would destroy the Labour party within weeks and Labour don’t want to compete on an even playing field. They want to be able to have the unions donate millions of pounds while the Conservatives spend time looking for more and more donors to help them.