Alan Johnson on Labour leadership vote and union links
4 February 2014 Last updated at 14:06 GMT
Labour's links with the unions are "precious and important", said a MP who is a former trade union leader and home secretary.
Alan Johnson said the party's links with unions would be "much healthier" if union members made "a conscious decision to pay the political levy".
He was speaking to Jo Coburn on the Daily Politics as Ed Miliband looks to scrap the voting system that elected him in 2010.