The gracious Imam of the Holy Land and descendent of Sheikhul Islam Muhammad ibn Abdulwahhab is simply reiterating a command given to him by the Prophet (saws) where he said:
It has been narrated by 'Umar b. al-Khattib
that he heard the Messenger of Allah (may peace be upon him) say: I will expel the Jews and Christians from the Arabian Peninsula and will not leave any but Muslim.
and Umar (ra) followed the Dear Prophet's command:
Umar expelled the Jews and the Christians from Hijaz. When Allah's Apostle had conquered Khaibar, he wanted to expel the Jews from it as its land became the property of Allah, His Apostle, and the Muslims. Allah's Apostle intended to expel the Jews but they requested him to let them stay there on the condition that they would do the labor and get half of the fruits. Allah's Apostle told them, "We will let you stay on thus condition, as long as we wish." So, they (i.e. Jews) kept on living there until 'Umar forced them to go towards Taima' and Ariha'.
So this Turkish "mufti" is a jaahil who doesn't even know that the prophet commanded this while the Mufti of Saudi Arabia is an aalim and is of course advising the Amir to follow the Prophet (SAW).