Response to Ofcom Consultation
13 October 2025
About UKCTA
1. This submission is made by the UK Competitive Telecommunications Association (UKCTA). UKCTA is a trade association promoting the interests of fixed line telecommunications and broadband companies competing against BT as well as each other, in the residential and business markets. Its role is to develop and promote the interest of its members to Ofcom and the Government. Details of membership can be found at www.ukcta.org.uk. Its members serve millions of UK consumers.
Harm from scammers abroad spoofing UK mobile numbers
2. UKCTA broadly agree with Ofcom’s assessment.
3. In passing, UKCTA would point out that whilst the calls in question may originate overseas, it is possible that some are initiated or controlled by fraudsters based in the UK.
Proposals to address consumer harm from scammers abroad spoofing UK mobile numbers.
4. UKCTA generally agrees with Ofcom’s proposals, which are broadly consistent with measures recently introduced by other European regulators. As the first point of ingress to the UK network, smaller operators will play a critical role in ensuring compliance and the effective implementation of these measures.
However, further clarification is required regarding the definition of “international gateway” and “communication provider”. Ofcom fails to recognise in their approach to this consultation that 07 mobile numbers are used by technologies beyond mainstream mobile networks. No consideration has been given to as to how or whether this new Guidance should be applied to virtual and cloud mobile services and the use of SIP trunking, for example. Solutions such as CAMEL routing solutions cannot be applied easily to such applications, if at all, which would result in CLI being permanently withheld on all calls originating outside of the UK. Ofcom should be mindful of this in coming to their final conclusion.
5. Such clarity is therefore essential to ensure that virtual and cloud service providers understand whether relevant technical solutions need to be identified and appropriately applied across all their relevant data interconnection trunks with international wholesale providers, and that no unintended gaps or inconsistencies arise in their application. Ofcom, should it decide to impose this requirement on virtual and cloud service providers, should be mindful that a reasonable implementation timescale in these use-cases for the virtual and cloud services space could, in practice, be far greater than that foreseen for a CAMEL-type implementation in the mobile network operator case.
6. The proposed backstop that international calls from abroad with mobile network CLIs should be allowed to proceed but with the CLI withheld is a basic step that all international gateway providers should be able to quickly implement and will help discerning consumers vet incoming calls.
7. Ofcom’s proposal that any mobile CLI present on an incoming call may be allowed to proceed if checks with the home network are successful will reduce the amount of frustration amongst the recipients of legitimate calls from those using their UK mobile phones whilst overseas. We would caution, however, that such a change may introduce a lower level of frustration. For example, when UK citizens traveling abroad make a call back to the UK using the roaming capabilities of an overseas network, should the call be placed over 2G or 3G visibility of their CLI could now be denied to the called party in the UK. Whilst UKCTA is of the view that this inconvenience is preferable by an order of magnitude to the current situation. This is an important point though, should Ofcom proceed and confirm these changes, and must be explained clearly to the public in announcing the new policy, particularly as in many holiday and business destinations, the availability of 4G and 5G networks is low to non-existent and will remain so for many years.
8. Whilst one may think that the backstop solution should be relatively straightforward and quick to implement (i.e. replacing the calling number with “number withheld”) Ofcom should recognise that the UK mobile network operators will need time to progress the implementation of any solutions they wish to deploy to maximise the amount of legitimate overseas roaming traffic that is allowed to route with the calling party number left in place. For example, it may be that they would implement further HLR CAMEL or VoLTE routing solutions with individual overseas networks to increase the proportion of calls that would be allowed to complete with the CLI visible. Going early with the backstop (i.e. replacing the CLI with “number withheld”) could result in a high proportion of legitimate roaming traffic being subjected to this mandated interference. Ofcom needs to work across both UK mobile network and international gateway providers to ensure the policy change is implemented in a controlled manner and to a balanced timescale.
9. We note that Ofcom is not mandating any particular solution but rather putting in place a requirements framework and leaving the implementation to the various UK mobile network and international gateway providers. UKCTA is supportive of such a voluntary approach noting that mobile providers will be under commercial pressure to enhance the experiences of their customers when making calls home from abroad, and of those they call.