“Today is an important turning point in the institutional life of our country,” said Hereditary Grand Duke Guillaume on Tuesday, marking his transition towards power.

With a handful of signatures and an oath before government officials, Guillaume has officially become Lieutenant-Representative in Luxembourg. This makes him the Grand Duke in all but name—and total power—though an abdication isn’t far off in the future.

Back in June, Grand Duke Henri made a shock announcement on National Day that he would hand over the majority of his power to his eldest son and heir on 8 October. It’s the first step towards abdication and a change in throne, so while Grand Duke Henri retains his title and the role of head of state, Guillaume is now empowered to carry out day-to-day functions and to represent Luxembourg on the global stage.

At the Grand Ducal Palace, Grand Duke Henri and Prime Minister Luc Frieden signed a document convening power upon Hereditary Grand Duke Guillaume. From there, the new Lieutenant-Representative gave a quick speech before travelling to the Chamber of Deputies, where he took an oath to uphold the constitution and carry out his role.

“As hereditary grand duke, I have had the opportunity over many years already to get acquainted with some of the grand duke’s duties and to undertake a considerable number of official tasks. The oath I have now taken as lieutenant-representative however obliges me not only to respect but also to defend at all times the fundamental values enshrined in our Constitution. I commit to this here before you and gratefully accept this responsibility.”

Traditionally, the Grand Dukes of Luxembourg begin their abdication processes with the announcement of their heir as Lieutenant-Representative. From there, roughly two to three years pass until the monarch officially abdicates.

Grand Duke Henri had been Lieutenant-Representative from March 1998 to October 2000 before ascending the throne.