Although Tristan da Cunha shares the +290 code with St Helena, residents have access to the Foreign and Commonwealth Office Telecommunications Network, provided by Global Crossing. This uses a London 020 numbering range, meaning that numbers are accessed via the UK telephone numbering plan. From 1998 to 2006, internet was available in Tristan da Cunha but its high cost made it almost unaffordable for the local population, who primarily used it only to send email. The connection was also extremely unreliable, connecting through a 64 kbit/s satellite phone connection provided by Inmarsat. From 2006, a very-small-aperture terminal provides 3072 kbit/s of publicly accessible bandwidth via an internet cafe.

Answer this question, if possible (if impossible, reply "unanswerable"): Who does Tristan Da Cunha share Global Crossing codes with?
unanswerable