Al-Aqsa as "exclusive property"

In his UN General Assembly meeting address, Mahmoud Abbas said:

Al-Aqsa Mosque and its surroundings, ladies and gentlemen, are the exclusive property of Muslims, and this was approved by the League of Nations in 1930, and we will not accept anything else, no matter the circumstances.

To what is he referring?

An International Commission was appointed by Great Britain following the 1929 riots. It was done with the approval of the Council of the League of Nations and its purpose was "to determine the rights and claims of Moslems and Jews in connection with the Western or Wailing Wall at Jerusalem".

Among its conclusions is this:

(3)  The Ownership of the Wall and of its Surroundings.

The Commission has to pronounce a verdict on the Jewish claims, and the Jews do not claim any proprietorship to the Wall or to the Pavement in front of it (concluding speech of Jewish Counsel, Minutes, page 908)...Subsequent to the investigation it has made, the Commission herewith declares that the ownership of the Wall, as well as the possession of it and of those parts of its surroundings that are here in question, accrues to the Moslems.  The Wall itself as being an integral part of the Haram-esh-Sherif area is Moslem property.  From the inquiries conducted by the Commission, partly in the Sharia Court and partly through the hearing of witnesses' evidence, it has emerged that the Pavement in front of the Wall, where the Jews perform their devotions, is also Moslem property.

I am not sure that this conclusion was "approved".

In any case, Mount Moriah was conquered and occupied by Moslem Arabs in 638 CE

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