Miss Belgium's UK citizenship; luckily, the British Nationality Act of 1981 is as clear as clear can be:

BNA 1981 Section 40 part 2:

The Secretary of State may by order deprive a person of a citizenship status if the Secretary of State is satisfied that deprivation is conducive to the public good.

BNA 1981 Section 40 part 3:

Subject to the provisions of this section, the Secretary of State may by order deprive any British citizen to whom this subsection applies of his British citizenship if the Secretary of State is satisfied that that citizen -

(a) has shown himself by act or speech to be disloyal or disaffected towards Her Majesty; or

(b) has, during any war in which Her Majesty was engaged, unlawfully traded or communicated with an enemy or been engaged in or associated with any business that was to his knowledge carried on in such a manner as to assist an enemy in that war;

So there we go, we can all move along, there is nothing more to se here.

wd sajid javid.