Can one wear new clothes on the Shabbat before Tisha B'Av? I guess by extension the Three weeks in general.
I understand that one shouldn't wear new clothes during the three weeks/9 days - does this apply on shabbat?
Shulchan Arukh, Orach Chayyim 551:6:
כלים חדשים בין לבנים בין צבועים בין של צמר בין של פשתן אסור ללבוש בשבת זה ( ואנו מחמירין מראש חודש ואילך):
New clothes, whether they are white or colored, whether made from wool or flax are forbidden to be worn on this Shabbat (and we are stringent not to do so from Rosh Hodesh Av onwards.)
See Magen Avraham who explains why and also cites an opinion that prohibits this during the entire 3 weeks.