Bhutan's King Jigme Singye Wangchuk has abdicated the throne after 34 years, and handed over power to his son Crown Prince Jigme Khesar Namgyel Wangchuck.
The 26-year-old Jigme Khesar becomes the fifth monarch and head of state of the Himalayan kingdom, which is set to adopt the system of parliamentary democracy in 2008.
The king issued a royal decree last Saturday announcing his decision to relinquish power in favour of his son.
"I am confident that a very bright future lies ahead for Bhutan with the leadership of a new king and a democratic system of government that is best suited for our country as enshrined under the Constitution," the decree said.
The transition was formally announced on Thursday at a special sitting of the Cabinet at the Royal Palace in Bhutanese capital Thimpu, Bhutan's official daily Kuensel said in a report.
Cabinet members and special guests including the chief justice, the speaker of the National Assembly and the chief election commissioner sat in a long and stunned silence after the king's announcement.
Prime Minister Lyonpo Khandu Wangchuk and members of the Cabinet endorsed the decision of the king to hand over the reins of the state to his son.
The government and people of Bhutan would serve His Majesty with dedication and loyalty, they said and expressed their full faith and confidence in their new king.
Jigme Singye Wangshuk had ascended the throne at the age of 16 and ruled Bhutan for 34 years.