PART V—DOMESTIC PROCEDURES FOR OTHER TYPES OF CO-OPERATION
Service of Documents and Appearance of Witnesses
89. (1) The Attorney-General shall assist in the
making of arrangements to facilitate a witness’s
attendance before the ICC if he is satisfied that—
(a) the prospective witness has consented to giving
the evidence or assistance requested; and
(b) the ICC has given adequate assurances where
Appropriate.
(2) The Attorney-General shall —
(a) approve and arrange the travel of the witness to
the ICC;
(b) obtain such approvals, authorities, and permissions as are required for that purpose, including, in the case of a person who although not liable to be detained in a prison is subject to a sentence—
(i) the variation, discharge, or suspension of the conditions of the person's release from prison; or
(ii) the variation or suspension of the person's sentence, or of the conditions of the person's sentence; and
(c) take such other action for the purposes of subsection (1) as he thinks appropriate.
Facilitating voluntary appearance of persons - national procedures for ICC proceedings
EDIT.