A Labour government will risk public sector strikes if it fails to increase workers’ pay, the president of the Trades Union Congress has warned, adding to the financial pressures facing Rachel Reeves if she becomes chancellor. Matt Wrack, who is also head of the Fire Brigades Union, urged Keir Starmer not to enforce tight public sector pay settlements, just hours after the Labour leader said his party would not meet the 35% pay rise demanded by junior doctors. The union leader’s comments, two days before Labour leaders are meeting trade unions to agree the party’s manifesto, indicates how difficult Labour may find it to manage trade union relations if it wins the election. Wrack said: “An incoming Labour government has to take account of the fact that people have struggled over 14 years, particularly on the back of the cost of living crisis. Something has got to be done to address that in people’s pay packets.” He added: “I get that they’re going to be under financial constraints and so on, but something will need to be done about it. Otherwise, you may see people taking further industrial action.” Starmer and Reeves are likely to face many financial pressures if they enter Downing Street next month, including historically high taxation levels, high government debt and struggling public services. The Labour leader got a round of applause on Tuesday night when he told a live television audience he would not raise junior doctors’ pay by 35% because the government could not afford it. But he is also likely to come under pressure from a range of other public sector pay unions to agree to above-inflation pay rises. Union leaders will meet Labour officials on Friday in London for the “Clause V meeting” to agree the party’s election manifesto. While pay is unlikely to feature in those talks, unions are preparing to push the Labour leadership not to drop key parts of its promises on workers’ rights. Labour’s package on employment protection, previously known as the New Deal for Working People and now rebranded Labour’s Plan to Make Work Pay, has been at the centre of discussions between the party and unions. Union leaders accused Labour of watering down its plans after it emerged the party planned to allow workers to sign zero-hours contracts if they wished, and wanted exceptions to its ban on “fire and rehire”. They reached an agreement over the package last month, however, with general secretaries demanding it not be diluted further. Wrack repeated that warning on Wednesday, urging Starmer to put the measures at the centre of his election campaign. “For good policy reasons, for vote-winning reasons and because it’s the right thing to do, he should stick with that, and he should resist pressure from business – or whoever – to water it down,” he said. The union leader said he expected some debate between unions and shadow ministers during the closed-door meeting on Friday, but he was confident the unions would be happy with the final manifesto, which will be published next week. “There will be an element of discussion debates and … negotiation in advance and during the meeting,” he said. But he added: “The leadership has said for a considerable time that this will be central to Labour’s campaign. I think that’s a positive message to take to working people and trade unions. “This is a brilliant opportunity to win votes, to enthuse people, and it needs to be central to the manifesto and the campaign that follows.”