As a member of the RF the Prince needs to inform the Foreign Office of any visits to foreign Heads of State/PM etc. The Prince had not done so and thus the Belgian PM wants to point out that rule once more to HRH.
I am however surprised that, if the Prince travels abroad no Belgian Ambassador or representative (Consulate General?) accompanies him or, in any case, is available to guide the Prince along the tricky rules of foreign diplomacy.
The Prince did something similar in 2011 when he travelled to Congo without even informing the government. As we all know, especially the relationship with the former colony is one that requires the uttermost caution, so the Prince really overstepped all rules there!
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