In a Hadith to the nearest meaning, hte Prophet PBUH said, “Whoever imitates a nation is from amongst them.” (‘Man ta shabbaha bi qawmin fahowa minhum’). Is this imitating the Kuffaar.
Answer:
With regard to pants and shirt, this mode of dressing has not been adopted by the learned and Allah-fearing, hence, attiring oneself in this fashion is not desirable. Moreover, a person would be deprived of the reward he would attain by adopting the Sunnah mode of attire. (Fataawa Mahmoodiyyah, vol.17 pg.349; Mahmoodiyyah)
and Allah Ta’ala Knows Best
Mufti Ebrahim Desai