The medal races in the women's and men's 470 classes of the Rio Olympics sailing regatta have been postponed because of lack of steady wind on the Sugarloaf Course off Flamengo Beach.

The Wednesday races were rescheduled for Thursday, which is the final day of the regatta. Medal races are also scheduled in the men's 49er and women's 49erFX skiff classes.

Britain's Hannah Mills and Saskia Clark have already clinched the women's 470 gold and need only to sail the medal race to collect it. Five teams have a chance at the silver and bronze, including Annie Haeger and Briana Provancha of the United States.

The men's medals are up for grabs.