TalkTalk has once again called for BT's wholesale broadband network - run by Openreach - to be run separately to the rest of the telecoms group.
Dido Harding, Chief Executive of TalkTalk, told attendees at an event organised by research group Enders Analysis that Openreach should split off from BT.
This is to ensure fair competition in the telecoms market and encourage network investment, she claimed.
As reported by the Financial Times, Ms Harding cited the break-up of airport operator BAA as a template for this process.
She claimed that the UK is falling behind on the construction of ultra-fast broadband networks, and that Openreach is not fit-for-purpose in its present form.
Ms Harding added that the firm, BT's infrastructure division, has never hit its service targets for TalkTalk, which provides broadband and phone services via BT's wholesale network.
But speaking at the same event, John Petter, Head of BT consumer, rejected TalkTalk's argument that BT should sell Openreach.
He said it is important to keep the division as part of BT, in order to encourage investment in the next-generation of ultra-fast broadband.
Mr Petter claimed network separation had failed in New Zealand, and there are clear risks to pursuing the same course of action in the UK.