Telecom dispute between Gibraltar and Spain

Direct telephone connections between Gibraltar and Spain were severed in 1969, when land communications between both territories were halted by the Spanish leader Francisco Franco, and were not restored until 1986. However, Gibraltar experienced restrictions after that date causing problems with its telecommunications system, as a direct result of the Spanish sovereignty claim.

Until 10 February 2007, Spain continued to impose restrictions on Gibraltar's ability to expand and modernise its telecommunications infrastructure. These included a refusal to recognise Gibraltar's International Direct Dialling (IDD) code (+350) which restricted the expansion of the Gibraltar telephone numbering plan, and the prevention of roaming arrangements for Gibraltar GSM mobile phones in Spain and vice versa. Following the signing of the Córdoba Accord between the Governments of Gibraltar, the United Kingdom and Spain in September 2006, these restrictions were removed with effect from 10 February 2007.

With the introduction of International Direct Dialling in the 1970s, Gibraltar was allocated its own IDD code, +350, by the International Telecommunication Union (ITU), which was accessible from any telephone network outside Spain. However, although physical connectivity existed between Gibraltar and Spain, the Spanish government prohibited its national operators from recognising this code.

When direct dialling from Spain was introduced, Gibraltar was treated as part of the Spanish telephone numbering plan, with callers from Spain having to dial 956 (the area code for the adjacent province of Cádiz) followed by the digit 7, and the subscriber's five digit landline number in Gibraltar, which could only begin with the digits 4, 5 or 7.

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Wikipedia