Imaam Ibn Taymiyyah has relevant words which we will mention here with slight modifications. He stated that the righteous predecessors held that Muslims should not seek the help of disbelievers in positions of power. To support this fact, they cited the sayings of Allaah (which mean):

• {O you who believe, do not take the Jews and the Christians as allies. They are [in fact] allies of one another.} [Quran 5:51]

• {Your ally is none but Allaah and [therefore] His Messenger and those who have believed - those who establish prayer and give Zakah [obligatory charity], and they bow [in worship]. And whoever is an ally of Allaah and His Messenger and those who have believed - indeed, the party of Allaah - they will be the predominant.} [Quran 5:5-56]

• {And those who disbelieve are allies of one another.} [Quran 8:73]

Abu Moosa narrated he informed ‘Umar Ibn Al-Khattaab that he had appointed a Christian scribe. ‘Umar reproached him and reminded him of the verse in which Allaah The Almighty Says (what means): {O you who have believed, do not take the Jews and the Christians as allies. They are [in fact] allies of one another.} [Quran 5:51] He then ordered him to replace the Christian scribe with a Muslim. Abu Moosa argued that he benefited from his writing while the scribe bore the sin of his religion. In turn, ‘Umar  explained to him that we must not honor them while Allaah The Almighty has degraded them with disbelief, nor should we dignify them while Allaah The Almighty has humiliated them, nor should we bring them closer to us while Allaah The Almighty has distanced them. [Ahmad: through a sound chain of narration]

Thus, we conclude that it is unanimously prohibited to assign disbelievers, irrespective of their sects and beliefs, to positions of authority.

Allaah Knows best.