Hong Kong's Hang Seng Index lost 22 points, or 0.09 percent, to open at 25,064 on Wednesday. This comes as oil prices fell again overnight, with markets focusing on the potential upside of renewed US-Iran diplomatic engagement. Global stocks were mixed, with the Nasdaq rising to a second straight record while the Dow retreated. Mainland stocks also opened mixed, with the Shanghai Composite Index down 0.02 percent and the Shenzhen Component Index up 0.14 percent.