Is it obligatory to read Qur’aan with the rules of Tajweed?

The correct view is that reading Qur’aan
with the rules of tajweed is not obligatory; tajweed is only a means of making
one’s recitation more beautiful. If a person reads and pronounces the letters
clearly with the vowels as marked, then this is sufficient. With regard to the
verse in which Allah, may He be exalted, says (interpretation of the meaning): “and
recite the Quran (aloud) in a slow, (pleasant tone and) style” [al-Muzzammil 73:4], that does not refer to tajweed; rather what is meant is to read it at a measured pace. End quote.