Gullit, 30, who scored twice in Milan's 7-3 win at Fiorentina in his first league appearance of the season, declined to elaborate on his motives for leaving the international scene.
Gullit signed for Milan in 1987 for a then record pounds 6m after making his name at home with Feyenoord and PSV Eindhoven. He made his national debut against Switzerland in 1981 and captained his country to the European Championship crown in 1988.
Gullit failed to impress at this year's European Championships in Sweden but is not known to be at odds with the new Dutch team manager, Dick Advocaat.
Speculation in Italy has it that his decision may be linked to the greater pressure for first team places at Milan this season.
Gullit was dropped for the first three league games of the season while his compatriots, Frank Rijkaard and Marco van Basten, retained their places.
The Netherlands' next World Cup qualifier is against Poland in Rotterdam on Wednesday week. The Dutch are also in England's group.
PAOK Salonika are cutting ties with supporters' associations after crowd violence at their ground last week prompted Uefa, European football's governing body, to impose a two-season ban on the Greek club.