Juncker denies he was the architect of Luxembourg tax regime Jean-Claude Juncker said that he was "not the architect" of Luxembourg's controversial tax regime as the new European Commission president attempted to head off questions about how the Grand Duchy became a hub for tax avoidance during his long tenure as prime minister. Mr Juncker, who took office as commission president this month, has come under fire after a vast document leak revealed the details of special tax arrangements between Luxembourg and 340 of the world's largest corporations, including Pepsi, Ikea and JPMorgan. These tax arrangements, many of which were sealed while Mr Juncker was prime minister of Luxembourg from 1995 to 2013, led to some companies in effect paying a tax rate of less than 1 per cent. The disclosure has threatened to create a political storm, with MEPs from the liberal ALDE group this week demanding a special committee to investigate EU tax havens. Mr Juncker addressed the issue for the first time on Wednesday in a hastily arranged press appearance at the commission headquarters in Brussels. "I am not the architect of the Luxembourgish model," he told reporters, adding that the Grand Duchy's tax authority had acted on an "autonomous basis," with little oversight from the finance minister - a job he also held for much of his time as prime minister. The commission president did concede he was "politically" responsible for the affair. More broadly, Mr Juncker pointed to a lack of "tax harmonisation" within the EU for contributing to the situation and called for the introduction of a "common tax base" across the economic bloc to address this. A "common tax base," he explained, would help reduce the differences between member states" tax codes, which companies can exploit to cut their overall tax bills. "If we can reach agreement on that, then many problems disappear," said Mr Juncker. The leak included 28,000 pages of documents from financial services group PwC, shedding light on its clients" arrangements with the Grand Duchy. Their contents were featured in a recent report by the International Consortium of Investigative Journalists. At Tuesday's press conference, Mr Juncker was asked if he would have still been selected as commission president had the revelations come to light earlier. "Yes, I would," he replied, and marched off the stage.