The primary language subtags allowed by the current IANA Language Subtag Registry are limited to ISO 639-1 and ISO 639-2 in the same way as they were limited by RFC 3066. This covers approximately 500 possible language subtags. ISO 639-3, scheduled for approval towards the end of 2006, will make available around 7000 more code elements for identifying languages. The working group will prepare an update to the Language Subtag Registry procedures to allow the use of 3-letter code elements from ISO 639-3 as primary language subtags or extended language subtags as appropriate. The working group will also deliver means to update the current IANA Language Subtag Registry with the newly available subtags. The working group will examine, and if necessary clarify or adjust, procedures and guidelines with respect to extended language subtags and variant subtags. Use cases include the identification of signed languages, transliterations, and transcriptions. The working group will also consider how the draft work on ISO 639-6 may relate to the future development of language tags. The working group will clarify text where necessary. It may also make adjustments to the registration process and the form of the registry if this is deemed appropriate based on ongoing registration and operational experience. These adjustments and clarifications are not expected to delay the progress of the work. Work on the drafts is planned to start before ISO 639-3 is fully approved and published. However, the WG will not finalize the drafts before ISO 639-3 is fully approved.