The ceremony, which included the chanting of holy stanzas and giving alms to Buddhist monks, was presided over by outgoing Prime Minister Prayut Chan-o-cha and his wife, Naraporn.
Members of the Privy council, the House speaker, the Supreme Court president, the Senate president, the Cabinet, the Secretariat of the PM, the Bangkok governor, and military chiefs also took part in the ceremony.
Prayut later participated in the royal ceremony at the Grand Palace's Wat Phra Si Rattana Satsadaram (Temple of the Emerald Buddha) and Amarindra Winitchai Hall and will preside over the candle-lighting ceremony to mark HM the King's Birthday at Sanam Luang at 7.20pm.