A trade union leader has called for “a degree of silence” from other union heads who have criticised Keir Starmer, after the head of Unite called for the Labour leader to “get a spine” and support striking workers. Paddy Lillis from Usdaw, which represents shopworkers, said comments like those from Sharon Graham, the Unite general secretary, were unfair and risked undermining Labour’s electoral chances. Starmer has been at odds with a number of union leaders after discouraging shadow ministers from joining picket lines, something a number of frontbenchers have nonetheless done. Starmer’s aides argue that while the party supports fair treatment and pay for workers, as a would-be party of government it cannot take a side in specific disputes. But speaking to BBC Radio 4 on Saturday, Graham criticised this approach: “I think that if they came out now strongly and said, ‘Hang on a second, these abhorrent profits that are going on, and what’s happening with the cost of living, this is what we think should happen,’ then I think they would very much get elected. “From my point of view, I think we are doing Labour a favour actually by saying, ‘Look, get a spine, stick up for workers.’” While Unite remain Labour’s biggest union financial backer, it has been a regular critic of Starmer. Last month, Graham warned about future funding for Labour, saying the party risked becoming “irrelevant to workers”. But in an interview on Sunday, also on Radio 4, Lillis criticised Graham’s approach. “I think it’s actually unfair,” he said. “I think Keir Starmer has demonstrated over and over again that he’s on the side of workers. He understands the industrial actions taking place at the minute. “We need to be, as a trade union movement and a labour movement, putting the blame squarely where it belongs. And that’s with this Tory government, who have been missing in action.” Lillis added: “I think there’s a degree of silence needed sometimes, and let the Labour leadership get on with taking the fight to the Tories and holding them to account for what’s wrong with this country in this moment in time.” Tensions between Starmer’s office and unions over support for strikes is likely to get worse in the coming months given the number of anticipated strikes looming as workers seek pay rises close to the fast-rising rate of inflation. Motions tabled by Unite and another big union, Unison, before the TUC congress next month have called for coordinated industrial action to help win better pay awards.