 « ancillary system ( as ) » means a system managed by an entity that is subject to supervision and / or oversight by a competent authority and complies with the oversight requirements for the location of infrastructures offering services in euro  as amended from time to time and published on the ecb website ( 1 )  in which payments and / or financial instruments are exchanged and / or cleared while the resulting monetary obligations are settled in target2 in accordance with guideline ecb / 2007/2 and a bilateral arrangement between the ancillary system and the relevant cb   « ancillary system central bank ( ascb ) » means the eurosystem cb with which the relevant as has a bilateral arrangement for the settlement of as payment instructions in the pm   « ancillary system interface ( asi ) » means the technical device allowing an as to use a range of special  predefined services for the submission and settlement of as payment instructions   « available liquidity » ( or « liquidity ) means a credit balance on a target2 participant s pm account and  if applicable  any intraday credit line granted by the relevant cb in relation to such account 