More than 18 million Freeview viewers will be required to retune their set-top boxes tomorrow (September 30) following an upgrade to the digital TV service.

The upgrade will give more viewers access to Channel Five and well as ensuring High Definition (HD) broadcasts can eventually be rolled out.

However, once the upgrade has taken place, viewers that can currently receive the channel will find they are unable to access it unless they re-tune.

"These are significant and necessary changes which will immediately bring Freeview viewers new channels, introduce new homes to exiting channels and prepare the platform for the future availability of Freeview HD," said Ilse Howling, managing director of Freeview.

Freeview also revealed that ITV3, ITV4 and BBC radio stations may also be affected, with a "small percentage" of viewers that recieve their signal via a relay trasnmitter will no longer be able to receive ITV3 and ITV4. Freeview said this was as a result of moving position on its platform.

Viewers can begin retuning their set-top boxes from 12pm on September 30.

For more information, visit www.freeview.co.uk.

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