NEW DELHI: Singapore Airlines (SIA) shares declined on the Singapore Exchange on Friday, a day after an Air India flight was involved in a crash in Ahmedabad.SIA, which holds a 25.1% stake in Air India, saw its stock drop 1.7% to SGD 6.91 by the midday trading break, after slipping as much as 2.1% earlier, according to The Straits Times.At least 265 people died when a London-bound Air India flight with 242 passengers and crew crashed into a medical college complex shortly after takeoff from Ahmedabad airport on Thursday.The Straits Times Index (STI) registered a 0.5% decrease as Asian markets reacted to Israeli airstrikes on Iranian targets, sparking concerns about regional stability in the Middle East and causing oil prices to rise significantly.Earlier on Thursday, Singapore Airlines said it is, “offering full support and all necessary assistance to Air India during this time”.“Singapore Airlines extends our deepest condolences to all passengers, crew members and their families affected by Air India Flight AI171. Our thoughts and prayers are with everyone impacted during this difficult time,”it added.SIA’s investment in Air India resulted from the latter’s merger with Vistara in November 2024. Before the merger, Vistara was a joint venture between Tata Sons and SIA. This stake gives SIA a direct role in India’s rapidly growing aviation market. SIA also has a codeshare agreement with Air India.