The following explanation was posted by Moshe Feiglin on his Facebook page. We have translated it into English:
In the introduction to his book "The Temple Mount," [former Chief Rabbi Shlomo] Goren wrote: "There is no doubt that when there is a risk of foreigners gaining control over Mount Moriah [the Temple Mount], it is permissible for Jews to enter the azara (inner courtyard) [under normal conditions forbidden by halacha], in order to prevent outsiders from gaining sovereignty of the Mount, because the presence of Jews on the Mount in this situation is considered a form of conquest [i.e., demonstrating sovereignty] which is greater than a foreign occupation."
Since I became a member of the Knesset, which means a representative of Jewish sovereignty in the land of Israel, I felt that these words of Rabbi Goren require me to enter anywhere in the Mount. This morning, I did not imagine how right I was. It turns out the the Dome of the Rock (not a mosque) was blocked two years ago for Jews and tourists. "Only Muslims are allowed," said a Waqf official nicely. I explained to the officer - the police had arrived - that by law an MK cannot be prevented from entering. [Members of the Israeli Knesset are granted the right to set foot anywhere within sovereign Israel.] The officer's response was astounding: "this place belongs to the Muslim Waqf." Here in the heart of the land of Israel, the Holy of Holies, Muslim sovereignty is actually the rule - simply on account of the fact that due to the sanctity of the location, Jews do not normally enter there.
It is important to emphasize that I am not calling on all Jews to start to ascend to the place where the Temple itself stood - but there is a difference between a member of the Knesset and the general public, but what happened this morning was a clear admission of a loss of Jewish sovereignty on the Temple Mount and we all need to change the situation.
I intend to contact the Attorney General today in order to clarify the status of sovereignty on the Temple Mount and the violation of the law of Israel.