By William SchombergLONDON (Reuters) - British finance minister Rachel Reeves will seek to shift the world's sixth-biggest economy, and Prime Minister Keir Starmer's government, onto a new course next week with big increases in public spending and tax.The Labour Party's first budget in 14 years will end months of speculation about how much Reeves and Starmer will borrow for infrastructure investment and how hard they will hit taxpayers.Reeves, a former Bank of England economist, has said she will not let public debt balloon, mindful of how former Conservative Prime Minister Liz Truss sent the bond market into a tailspin two years ago with unfunded tax cut plans.Reeves' budget on Wednesday is likely to include an array of revenue-raising changes, a prospect that has worried households and business already on edge about Labour's plan to give workers more protections in their jobs."We've never seen this level of interest in a budget," said Amanda Tickel, global leader for tax and legal policy at accountancy firm Deloitte."It's a new government which will potentially have to cast its net wide and it's also about the magnitude of the challenges," she said. "We can expect a significant departure from the past."Voters turned to Labour in July's election largely for its pledge to fix public services from over-crowded prisons and crumbling public housing to the over-stretched health service.But Labour's support in opinion polls has been hit by the government's warnings of a painful budget while cuts to fuel subsidies to pensioners angered voters at a time when Starmer's acceptance of expensive gifts from donors was in the headlines.source: investing.com