AOL, Apple, Facebook, Google, LinkedIn, Microsoft, Twitter and Yahoo joined together to propose principles for reforming government surveillance laws and practices. The companies issued an open letter to U.S. President Barack Obama and Congress to bring in reforms and restrictions on surveillance activities.

In the letter, the tech giants highlight the need to reform government surveillance practices worldwide. The companies add that they understand that governments need to protect their citizens' safety and security. But they urge US to make reforms that ensure that government surveillance efforts "are clearly restricted by law, proportionate to the risks, transparent and subject to independent oversight."

The 'Reform Government Surveillance' campaign details five concerns including limiting governments' authority to collect users' information, transparency about government demands and avoiding conflicts among governments.

Obama said last week he intends to propose NSA reforms to reassure Americans that their privacy is not being violated by the agency.