Microsoft will allow foreign customers to have their personal data stored on servers outside the US, breaking ranks with other big technology groups that until now have shown a united front in response to the American surveillance scandal.

Brad Smith, general counsel of Microsoft, said that although many tech groups were opposed to the idea, it had become necessary after leaks that showed the National Security Agency had been monitoring the data of foreign citizens from Brazil to the EU. “People should have the ability to know whether their data are being subjected to the laws and access of governments in some other country and should have the ability to make an informed choice of where their data resides,” he told the Financial Times.

The scandal over the NSA’s illicit internet surveillance and the bulk collection of phone records has caused tension between the US and even some of its closest allies. The revelations sparked a global backlash, from calls for tighter privacy rules in Europe to a draft law in Brazil that would require all data about citizens to be held inside the country. Internet companies argue that this would Balkanise the internet, turning it into a patchwork of national or regional systems.