Part II
Extradition
CHAPTER I
Extradition from Portugal
Section III
Special procedural rules for cases of provisional arrest
Article 64
Non requested provisional arrest
3. The arrest shall be terminated after 18 days unless a reply is received to the question mentioned in the preceding paragraph, and it shall be terminated after 40 days if a positive reply is received but not followed by an extradition request.
Provisional arrest - release - ICC proceedings
EDIT.