The red lion is the official ensign for ships registered in Luxembourg. It is used for river and sea shipping, as well as for aviation. This flag is based on the coat of arms of Luxembourg (a banner of arms) and is used as the ensign to avoid the possibility of Luxembourg's ensign being confused for that of the Netherlands. Ten white and blue stripes serve as the field for a red lion with a yellow tongue, claws and crown.
The resemblance of the Luxembourgish flag with the Dutch flag has given rise to a national debate to change it.
On October 5, 2006, MP Michel Wolter introduced a legislative proposition to replace the current red-white-blue national flag with the red lion ensign. He argued that the current flag was commonly confused with that of the Netherlands and that the red lion on the other hand was more popular, more aesthetic and of greater historic value. Wolter also claimed he had personally discussed the matter with some three hundred people, most of whom expressed their support for his initiative. On the other hand, many national politicians (including leading members of Wolter's own CSV) and VIP's have expressed astonishment in the local media concerning both the timing and necessity for such a change. The only political party to express support for Wolter's initiative was the nationalist and populist ADR.
On October 24, 2006, a local initiative called Initiativ Roude Léiw ("Red Lion Initiative") held a press conference explaining their intention to support Wolter's project on a non-partisan basis. Their first actions would include distribution of red lion bumper stickers, a petition and a poll. During sporting events like the Tour de France supporters for Luxembourg participants now overwhelmingly use the Ensign instead of the Flag.
In 2015, a citizen submitted a formal petition to the Chamber of Deputies to replace the current national flag with the Roude Léiw.
For historic reasons, the adjacent Belgian province of Luxembourg uses a flag that also features a lion superimposed on horizontal stripes. Elsewhere, similar designs can also be found, for instance in the Belgian city of Bruges and the German state of Hesse.