Britain's shadow chancellor John McDonnell is about to unveil the Labour Party's backing for an extremely popular tax reform amongst the left-wing electorate — the so-called "Robin Hood Tax." Campaigners propose that the Financial Transaction Tax (FTT), more commonly known as the Robin Hood Tax, places a 0.05% on trades involving stocks, bonds, foreign currency, and derivatives. However, the European Commission is aiming to launch the FTT in January 2016 with slightly different tax calculations — 0.1% on shares and 0.01% on bond transactions where at least one of the parties was based in the EU. The Robin Hood Tax campaign group estimates that if this levy was applied to the financial sector, it could raise £250 billion ($380 billion) annually across the world. The leader of the Labour party Jeremy Corbyn wrote an editorial on Europe in the Financial Times last week about how the FTT was central to the left-wing party's push for Britain's negotiation with Brussels over Britain's European Union membership. However, today the shadow chancellor will officially deliver the Labour's economic manifesto at its party conference, the first time since Corbyn won the Labour leadership contest by a landslide vote earlier this month. McDonnell told the BBC on TV this morning: Robin Hood tax at the moment is Labour Party policy on the basis of if we can introduce it globally, and that's been Labour Party policy for some time now. However, what we are saying is today we are going to launch a review of our taxation system, we are going to bring the greatest economic minds in the world to bear on that issue, we are going to consult with the British people and then we will arrive at a decision on the way forward. The right-wing Conservative government, the financial sector, and various business groups are heavily against the FTT. In February last year, research by consultancy London Economics said that ordinary savers would instantly lose £3 billion ($4.6 billion) as the levy on personal savings would be immediate. In 2013, the same research body released a report, also commissioned by the City of London Corporation, that said Britain could potentially pay £4 billion ($6.1 billion) in more borrowing costs from the Robin Hood Tax, even if it didn't end up signing up to the plan. The Tory-led government hates the tax proposition so much that UK Chancellor George Osborne even launched a legal suit against the FTT plan which was adopted by 11 EU states. Germany, France, Italy, Spain, Belgium, Austria, Portugal, Greece, Slovenia, Slovakia, and Estonia all have signed up to implementing the FTT out of 28 nations in the bloc. In 2014, Britain's lawsuit was rejected by the EU's Court of Justice, which said Britain's challenge against the FTT was "premature." "The government is determined to continue to ensure that the interests of countries outside of the single currency, but inside the single market, are properly protected," said a UK Treasury spokesman at the time. Join the conversation about this story » NOW WATCH: The one thing you can add to coffee for even more energy in the morning