# Commission Implementing Regulation (EU) No 923/2012 of 26 September 2012 laying down the common rules of the air and operational provisions regarding services and procedures in air navigation and amending Implementing Regulation (EU) No 1035/2011 and Regulations (EC) No 1265/2007, (EC) No 1794/2006, (EC) No 730/2006, (EC) No 1033/2006 and (EU) No 255/2010 (Text with EEA relevance), Division (a): In order to provide air traffic control service, an air traffic control unit shall:

Extent: E+W+S+N.I.

(1)be provided with information on the intended movement of each aircraft, or variations therefrom, and with current information on the actual progress of each aircraft;
(2)determine from the information received, the relative positions of known aircraft to each other;
(3)issue clearances and information for the purpose of preventing collision between aircraft under its control and of expediting and maintaining an orderly flow of traffic;
(4)coordinate clearances as necessary with other units:
(i)whenever an aircraft might otherwise conflict with traffic operated under the control of such other units;
(ii)before transferring control of an aircraft to such other units.

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Source: https://www.legislation.gov.uk/eur/2012/923/annex/section/8/division/SERA.8005/division/a (the official version)
Page: https://openlegislation.uk/eu-regulation-2012-923/annex/section-8/division-SERA.8005/division-a
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.