President Rodrigo Duterte and U.S. President Barack Obama on Thursday night joined Thailand in mourning the passing of King Bhumibol Adulyadej.

In a statement, Presidential spokesperson Ernesto Abella expressed Duterte's deepest condolences to the family of the late king.

"We are well aware that King Bhumibol was well-loved and held in utmost respect and veneration by the Thai people and by those whose lives he had touched during his lifetime. We extend our deepest condolences to his family and all those he left behind," Abella said.

He also wished Crown Prince Maha Vajiralongkorn the best in his upcoming duties as the new king.

"At the same time, we wish his son and heir apparent, Crown Prince Maha Vajiralongkorn, all the best as he assumes the duties and responsibilities as Thailand's new king," Abella said.

"We are certain that as the country's titular leader and guiding light, he will be able to enhance Thailand's stature in the region and help the country achieve lasting peace and continued economic and social progress in the years ahead," he added.

Obama also offered condolences to the Thai people.

"As the revered leader and only monarch that most Thais have ever known, His Majesty was a tireless champion of his country's development and demonstrated unflagging devotion to improving the standard of living of the Thai people," Obama said in a White House statement.