Samsung's proposal for using its Knox-enabled smartphones on government's classified network has been approved by the U.S. authorities.

Samsung, the leader of smartphone business, is deemed secure in the eyes of the United States government. On Tuesday, the National Information Assurance Partnership (NIAP), NSA division that analyses IT products for government use, approved the use of Knox-enabled Samsung smartphones on the classified U.S. government network. This is a major victory for the South Korean tech giant as it is struggling to push the sales of its smartphones due to severe dominance from Apple's iPhones and other low-priced phones. But Samsung is the only smartphone company to have won both Defense Information Systems Agency (DISA) and Commercial Solutions for Classified (CSfC)'s approval.

The latest approval by the National Security Agency comes after Samsung mobile devices were approved by the Department of Defense to carry out sensitive, but unclassified information. With the use of Samsung phones for government's classified data, Samsung phones have earned the reputation of being the most secure phones around.

According to ZDNet, which originally broke the news via its Korean sister site, the approved Samsung phones listed on the CSfC program listing includes the Galaxy note 4, Galaxy S4, Galaxy S5, Galaxy Note 3, Galaxy Note 10.1 2014 Edition, Galaxy Note Edge, Galaxy Alpha, Galaxy tab S 8.4, Galaxy Tab S 10.5 and the Galaxy IPSEC Virtual Private Network (VPN) Client.

"The inclusion of Samsung mobile devices on the CSfC list proves the unmatched security of Samsung Galaxy devices supported by the Knox platform," JK Shin, CEO and president of IT and mobile business, Samsung, said in a press statement, Tuesday. "At Samsung, we continue to address today's increasingly complex security challenges, and are committed to delivering the most reliable mobile platform satisfying the needs of professionals in all industries, from SMBs and enterprises to governments and additional regulated markets."

All devices selected for classified U.S. government use are equipped with Samsung's proprietary Knox security software. Earlier this year, Google also agreed to integrate its next version of Android mobile operating system with Knox, a move which was publicly shown down by BlackBerry's CEO John Chen.