Thailands Crown Prince flew back to the kingdom on Friday after a fortnight overseas, palace sources confirmed, although there is still no date for when he will officially succeed his father.
Crown Prince Maha Vajiralongkorn, 64, left Thailand last month, some two weeks after his father King Bhumibol Adulyadej died ending a seven-decade reign.
His death has sparked mass displays of grief and left the politically-divided nation without a rare pillar of unity.
Although Vajiralongkorn is the named successor, he surprised many and veered from tradition by asking to delay his proclamation as king in order to grieve with the nation, according to the junta that currently runs the country.
The prince, who has yet to attain his father's widespread popularity, spends much of his time overseas, especially in southern Germany.
Two palace sources told AFP the prince flew back to Thailand on Friday morning and would attend a military function in the evening and preside over a graduation ceremony at Bangkok's Thammasat University this weekend.
On Monday he is slated to attend an annual cultural event in Pattani, a Muslim-majority province in Thailand's insurgent-torn far south, according to an official schedule seen by AFP.
The government has not provided a timeline for when he will formally ascend the throne.
But they have sought to tamp down any doubts over succession, suggesting the Crown Prince will be named king in the near future.
Under Thai law, a successor is initially proclaimed king by parliament. He is then coronated once the previous monarch is cremated, often months later.
A strict royal defamation law and layers of official opacity make it difficult to confirm facts about Thailand's monarchy and all but impossible to openly debate its role.
All media based in Thailand must self-censor to avoid falling foul of the lese majeste law, which punishes criticism of the monarchy with up to 15 years in prison per infringement.
Thailand's arch-royalist military government has ramped up use of the law, with a particular focus on online dissent, since coming to power in its 2014 coup.
Authorities and ultra-royalist vigilante groups have further stepped up enforcement since Bhumibol's death.
An initial 30-day mourning period for King Bhumibol ends on November 14, although civil servants and many more will mourn for a year until Bhumibol is cremated.