Which mobile operator in the UK has an analogue of Multifon?

Question

SIP

Task: to use IP-telephony on an existing English cell number (+44 7xxx) like Megaphone on Multiphone. Transferring an existing mobile number to another mobile operator is not a problem, the only question is - which mobile operator (vodafone, O2, etc.) provides VoIP telephony services? Thanks in advance!

Answer 1

Connection via SIP can be physically provided by all mobile operators. But for various reasons, the vast majority are encrypted as partisans during interrogation by the Gestapo. With whom it was possible: Megafon, Life, Kievstar
Other operators can meet halfway for corporate subscribers.
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