The US Federal Communications Commission (FCC) began collecting information from operators about how much Huawei and ZTE equipment is currently in use in their networks, as it presses ahead with an effort to force the replacement of their kit.

Operators were asked to report whether they own or employ equipment and services from the vendors and, if so, what these are. They are also being asked for details of the original purchase and installation costs, along with estimates of how much it would cost to remove and replace it.

Reporting is mandatory for operators which receive federal subsidies from the FCC’s Universal Service Fund (USF) and voluntary for those which do not. Responses are due by 22 April.

The FCC branded Huawei and ZTE as security threats in 2019 and moved to ban the use of their gear in domestic networks. It wants operators receiving government funds to replace any equipment already in use.

In a statement, FCC chairman Ajit Pai said the regulator is “moving forward quickly to identify where equipment and services from these suppliers are embedded in our communications networks and, where they do have a foothold, to be in a position to help remove them”.

The FCC said the inventory take will help it better assess reimbursement requirements for removal of the equipment.

In its original order, the regulator tentatively estimated the average cost to replace existing kit would fall between $40 million and $45 million per operator.