King Bhumibol Adulyadej died on Thursday and the crown prince wants more time to mourn his father.
Former Prime Minister Prem Tinsulanonda is standing in as regent.
Current Prime Minister Prayuth Chan-ocha sought to reassure Thais about the succession in a TV address on Saturday, saying they should not worry.
This issue was discussed when Crown Prince Vajiralongkorn summoned the regent and Gen Prayuth for an audience, according to Gen Prayuth.
