The two international big hitters, who have recently worked alongside each other on the high-profile Solomon R Guggenheim Saadiyat Island scheme ( Trio of starchitects joins Zaha in Abu Dhabi ), are being backed by competing bidders hoping to get their hands on the famous Customs House site between Giudecca island and the Grand Canal.
Pinault appointed Ando to come up with a new design while the Guggenheim again turned to Hadid to carry out its design work.
The two teams entered a contest to 'win' the lease of the building back in 2006. Confusingly, however, the local authorities said the two teams should work together to bring the project forward.
In the last few weeks the alliance has looked increasingly shaky and comments from Pinault's right hand man that a collaboration would be 'unrealistic' have effectively pitted the two architects against each other.
The Italian government is expected to make an official ruling about the future of the site later this month.