A schedule for the routine maintenance of the international public telephony circuits linking any two countries(including speech circuits of Signalling System No. 6),is drawn up by bilateral agreement between the technical services1) of the countries concerned. The programming of the tests to be performed within the agreed scheduled time is the responsibility of each Administration.It is for the circuit control stations to ensure that the routines are carried out within the agreed schedule except as allowed for in § 2.5 below.