Prime minister Gordon Brown has won President Obama's support to a 'global new deal', which will see the world's biggest economies uniting on a regulatory action to deal with tax havens. Obama has said he wanted the summit next month to look at how the G20 countries can 'in a co-ordinated fashion, stimulate their economies,' The Times reports. The move comes at the same time that US senator Carl Levin has launched a strengthened Stop Tax Haven Abuse Act, which has received support of Obama, Tax-news.com reported. 'Offshore tax haven and tax shelter abuses are undermining the integrity of our tax system and increasing the tax burden on middle income families,' Levin said. 'We cannot tolerate $100bn (£71bn) in offshore tax abuses burning a hole through our budget each year. We can fight back against secrecy jurisdictions and shut down offshore tax abuses if we have the political will. This bill provides a powerful set of new tools to clamp down on offshore tax and tax shelter abuses.'