Thai regulator the National Telecommunications Commission (NTC) has ordered incumbent fixed line operator TOT to start negotiating network access charges with mobile operator DTAC or risk penalties ranging from fines to the loss of its licences, reports the Bangkok Post. Yesterday was the deadline the regulator had set for TOT to start talking with DTAC but the state-owned telco has apparently still not responded to requests to discuss the months-old dispute. DTAC, which holds a build-transfer-operate (BTO) concession from TOT’s sister company CAT Telecom, previously petitioned the Administrative Court for emergency protection after TOT threatened to block access to its network for three million new DTAC mobile phone numbers. Fellow privately-owned cellco True Move, also a CAT concessionaire, sought similar protection. DTAC and True Move stopped paying access charges to TOT in November last year, arguing that they should pay cost-based interconnection charges instead, to comply with new NTC rules. TOT last year earned access charge revenues of THB14 billion (USD450 million).