Will not happen, if you have visited UAE or KSA you will know that Govt controls every mosque and its imam are posted with Govt approval, Imam Kaaba has no value, and even if by any Miracle he does put his Standing with Allah SWT on forefront to give such a call, than KSA Shurta will arrest him and he will be forced to take back the call. Don't expect any help from anyone, even the Taliban who now controls a country with much significant Military gear has not even issue a statement, but I bet there are clashes everyday on Torkhum Border with Punjabi Daal Khor Pakistani's, I expect help from no one except Allah, Allah will do justice with every Israeli and its supporters in the fashion he seems fit, remember they Plan, and Allah Plans and Allah is the best Planner, maybe there is some hidden Hikmaat which we can not see it but only Allah knows...
Also, we have to keep Rasool Allah's prophecies in mind that the Al-Aqsa mosque will get destroyed and Jews will build their 3rd Temple, In the times of Prophet when he was alive, his biggest enemies were Pagans of Mecca, only major clash with Jews were with Banu Qureza, and yet Jews are mentioned that Muslims will fight before the end times, it was a prophecy which would not make sense back in his time, Jews who's are mentioned so many times in Quran, and Mosa AS who is among the top Rasool's, and yet his nation will be locking horns with Muhammad's nation, who would have thought ? but look how Jews turned against the Muslims who throughout history protected them from brutal Prosecution from Catholics and Christians. Of course if I put my human sentiment aside of all that human loss and destruction, I am witnessing Prophet's words unfolding right before my eyes, If I was a Jew I'd be scared that what their nation has become, and doing exactly what was prophesized. I am waiting for the day when they bomb Al-Aqsa and destroy it to finally build their temple, and anyone who have studied the Hadith will know it won't end well for them even after building that temple.