Britain is bracing for mass disruption to schools, hospitals and border controls on Wednesday as up to two million public-sector workers walk out over proposed pension reforms in what is set to be the biggest walkout for a generation. The proposed reforms have prompted wide anger among public sector workers, many of whom say they are bearing the brunt of austerity measures brought in to try to rein in Britain’s deficit. Negotiations between the government and unions to try to ward off the industrial action broke down in the days leading up to the strike. Travelers seeking to enter Britain may encounter long lines at ports and airports, as many staff who normally carry out border control checks will be on strike. The Home Office said “robust arrangements” were in place to compensate, with managers, contractors and foreign staff trained up to fill the gap. “Securing the border is our priority and over the last weeks and months we have considered all options to ensure we are prepared for union action,” UK Border Agency chief executive Rob Whiteman said in a statement. “We always aim to minimize any disruption caused by the decision of unions to strike, but travelers could see longer waiting times at some ports and airports.” Meanwhile, Chancellor George Osborne, the British finance minister, announced a pay raise cap of 1% for public sector workers for two years after the current pay freeze ends, as he lowered growth forecasts in an assessment of the economy Tuesday. He said that while Britain had regained stability after the financial crisis, it had been “hit by a series of shocks which have significantly weakened the economic and fiscal outlook.” His report blames higher-than-expected inflation, the uncertainty created by the crisis in the eurozone and the impact of the 2008-2009 financial crisis, the full scale of which is now clearer. The Labour Party argues that the poor growth is a result of the government’s spending cuts and tax hikes, which it says have squeezed the recovery too hard. Brendan Barber, general secretary of the Trades Union Congress (TUC), said Tuesday that public-sector workers would not accept the proposed reforms. “Public servants are no longer being asked to make a temporary sacrifice, but accept a permanent deep cut in their living standards that will add up to over 16% by 2015 when you include pay and pension contributions,” he said. “It is no wonder that the government has alienated its entire work force, who are coming together in unprecedented unity tomorrow to take a stand against such unfair treatment.” The TUC estimates that as many 2 million will walk out, including teachers, nurses, probation officers, civil servants, cleaners and paramedics. It says about 30 unions balloted their members on strike action, some of them for the first time. Those striking are angered by proposed pension reforms that will see them asked to contribute more money, work longer hours and accept changes to the way their pensions are calculated.