Sonam completed five years of walking the red carpet at the film festival for the brand last year, read a statement.
It is still not confirmed on which date the duo will walk the red carpet.
The 2016 Cannes International Film Festival is scheduled to take place from May 11 till May 22.
Sonam was last seen on-screen playing the title role in Ram Madhvani's biographical thriller film 'Neerja'.
Aishwarya, meanwhile, can next be seen in 'Sarbjit', which is slated to release on May 20.