Chinese telecoms giant Huawei is suing the U.S. government over Washington's ban on its products.<br />The firm says it has filed a lawsuit in a court in Texas and seeking it to have the ban overturned.<br />The U.S. says the restrictions are in place due to national security concerns, claiming Huawei's products were being used to spy for the Chinese government.<br />Huawei denies that is the case and says the ban is unconstitutional. <br />
