Statements of Mirza Basheer-ud-Din, Ghulam Ahmad’s son and successor, including what he wrote in his book Ayena-e-Sadaaqat (p.35):

“Verily, every Muslim who does not pledge allegiance to the Promised Messiah (Mirza Ghulam Ahmad), whether he heard of his name or not, is a disbeliever and outside the fold of Islam!” He is also quoted in the Qadiani periodical, Al-Fazl (30th July 1931) as reporting from his father, Ghulam Ahmad himself that he said:

“We disagree with the Muslims in everything: concerning God, the Messenger, the Qur’aan, prayer, fasting, hajj and zakaah. There is a fundamental difference of opinion between us in all of these things!”

https://www.masjidattaqwa.co.nz/ahmadiyya/