Chancellor of the Exchequer George Osborne warned Sunday that Britain's economic recovery was on course but far from completion as he prepared to deliver his annual budget this week. Osborne said Britain was not exporting, investing, building or making enough to secure the revival. "The message I'll be giving in the budget is that the economic plan is working but the job is very far from done," he told BBC television. Osborne will deliver his fifth annual budget in parliament on Wednesday, and is expected to uphold the coalition government's deficit-reducing course as the British economic recovery strengthens. "We need to build a resilient economy and that means addressing the long-term weaknesses in Britain," the Conservative chancellor said. "We don't export enough; we don't invest enough; we don't build enough and we don't make enough." He said Britain needed to link itself to emerging markets and support business investment. "These aren't new features of the British economy -- they've been historic weaknesses that the very big economic recession has exposed," Osborne said. "We've got to go a lot further. We've got to make sure we're really getting to the bottom of what it is that provides economic security for the people of this country. Britons need "the economic security of knowing you've got a job, the country's earning its way in the world, that we can deal with debts and we've got public finances under control," he said. Asked about whether the threshold for the 40 percent income tax band -- now swelling with middle-income earners -- would be raised from the £31,866 ($53,050, 38,150 euros) fixed for the 2014-15 financial year, Osborne refused to divulge details. "I'm a low-tax Conservative. I want hard-working people on all of these incomes to keep more of their incomes tax-free," he said. "We do have a lot more difficult decisions to come because the truth is this country got itself heavily into debt. It racked up a very big budget deficit," he warned, on future tight budgets. Osborne and London Mayor Boris Johnson are seen among the potential candidates for the next Conservative leader after Prime Minister David Cameron, but the chancellor played down talk of hostility between them. He said such stories were "just not true", and he would "absolutely" welcome Johnson back into parliament. Johnson's term as London mayor expires in 2016, a year after the next general election. Osborne also announced that a new garden city -- a satellite new town planned around green spaces that will be the first in nearly a century -- of 15,000 homes would be built east of London at Ebbsfleet, which has a stop on the high-speed rail line linking London with Paris and Brussels.