Prime Minister Prayut Chan-o-cha said he had been granted an audience with the crown prince, who told him he would like to take some time to grieve with the nation before accepting the invitation to become the new king.
"His Royal Highness would like to wait for an appropriate time," Gen Prayut said.
At 9pm on Thursday, the National Legislative Assembly acknowledged the passing of His Majesty King Bhumibol Adulyadej and its president will invite His Royal Highness Crown Prince Maha Vajiralongkorn to ascend the throne by law and tradition shortly.
The Royal Household Bureau statement on the king's passing was read out at the NLA and its members held a moment of silence for nine minutes. Constitutionally, the next step is for NLA president to invite HRH Crown Prince Maha Vajiralongkorn to become the new king.
According to Section 23 of the 2007 constitution, when the throne becomes vacant and the king has already appointed his Heir under the 1924 Palace Law on Succession, the cabinet shall notify the Parliament president, who will convene members for acknowledgement.
The parliament president will then invite the Heir to ascend the throne and proclaim him King, according to the provision.
Since there is no Senate or House of Representatives at the moment, the 250-member National Legislative Assembly will act as parliament.
His Majesty King Bhumibol Adulyadej appointed His Royal Highness Prince Vajiralongkorn as the Heir to the Throne on Dec 28, 1972 after which he became His Royal Highness Crown Prince Maha Vajiralongkorn.
Although the 2007 charter was scrapped by the 2014 coup, the 2014 interim charter uses its chapter on the King as a reference.
Earlier on Thursday, the NLA postponed its scheduled Thursday agenda indefinitely. Mr Surachai told the assembly that NLA president Pornpetch Wichitcholchai and NLA vice president Peerasak Porjit proposed the postponement due to a very necessary reason. Mr Surachai did not elaborate.
As tension mounted throughout Thursday, Prime Minister Prayut Chan-o-cha cancelled a weekend trip to Goa in India for a regional summit.
He was originally scheduled to attend the Bay of Bengal Initiative for Multi-Sectoral Technical and Economic Cooperation (Bimstec) and the BRICS (Brazil, Russia, India, China and South Africa) meeting on Oct 14-17.
The prime minister has also withdrawn from a dinner marking Police Day in the evening. The event was subsequently cancelled.
Later, the interior permanent secretary told governors and district chiefs to prepare for a nationwide video conference with Bangkok at 7pm, but the order was later scrapped.
