Al-Mumtahanah 60:1

Ya ayyuha allatheena amanoola tattakhithoo AAaduwwee waAAaduwwakum awliyaatulqoona ilayhim bilmawaddati waqad kafaroo bima jaakummina alhaqqi yukhrijoona arrasoola wa-iyyakuman tu/minoo billahi rabbikum in kuntum kharajtumjihadan fee sabeelee wabtighaa mardateetusirroona ilayhim bilmawaddati waana aAAlamu bimaakhfaytum wama aAAlantum waman yafAAalhu minkum faqad dallasawaa assabeel

O you who have believed, do not take My enemies and your enemies as allies, extending to them affection while they have disbelieved in what came to you of the truth, having driven out the Prophet and yourselves [only] because you believe in Allāh, your Lord. If you have come out for jihād [i.e., fighting or striving] in My cause and seeking means to My approval, [take them not as friends]. You confide to them affection [i.e., instruction], but I am most knowing of what you have concealed and what you have declared. And whoever does it among you has certainly strayed from the soundness of the way.

O you who believe, do not take My enemies and your enemies for friends, expressing love with them, while they have rejected the Truth that has come to you, expelling the Messenger and your selves (from Makkah) merely because you have faith in Allah who is your Lord, if you have set out to do Jihād (struggle) in My way, and to seek My pleasure. You express love with them secretly, while I know what you have concealed and what you have revealed. Any of you who does this has missed the straight path.